What The Killer Left Behind

Summary

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20/20 Podcast – “What The Killer Left Behind”

Podcast by ABC News | January 31, 2026

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Overview: Main Theme & Purpose

This episode of 20/20 examines the harrowing true crime case of Amanda Plass, a beloved 20-year-old woman brutally murdered in her Chicopee, Massachusetts apartment in 2011. Through in-depth interviews and the voices of Amanda’s family, friends, investigators, and even the accused, the episode explores the winding, tension-filled investigation—the major false leads, a unique clue hiding in plain sight, and the determined quest for justice led by Amanda’s relentless mother. The case ultimately pivots on the forensic evidence Amanda "left behind," and the tenacity of all those who refused to abandon her memory.

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Key Discussion Points & Insights

The Discovery & Aftermath of Amanda Plass’s Murder

• Initial Shock and Scene Description

  • Amanda fails to show up for her waitressing shift at Friendly’s, alarming family and coworkers ([04:08]).
  • Seth Green, Amanda’s boyfriend of just one week, discovers her body—stabbed multiple times, throat slit—on her kitchen floor; he is inconsolable and frantic ([04:37], [05:56]).
  • Scene is described as “brutal,” indicative of a heated, violent struggle ([06:21]; [06:39]).

• Family Devastation

  • Amanda’s mother, Michelle Penna, and sister, Amy Lee, recount the agony and disbelief upon learning of the murder ([07:31], [08:12]).
  • Michelle’s struggle with not only grief but also with practicalities—funeral arrangements, expenses, the search for answers ([08:39], [09:07]).

Early Investigation: Suspects & Dead Ends

• Everyone Is a Suspect

  • “Every single person in her life was a suspect. Everybody.” – Amy Lee ([01:33], [09:55])
  • Police immediately focus on Seth Green due to the nature of the crime and his proximity, especially after he admits a work knife is missing ([10:01]–[10:39], [16:24]).

• Seth Green’s Ordeal

  • Seth describes being interrogated and suspected, even though he called 911 and was distraught ([16:52], [24:03]).
  • Ultimately, Seth’s timeline, DNA, and shoe size do not match the evidence ([23:24]).

• Other Leads: Ex-Boyfriend Jesse, Friend Mercedes Benz

  • Amanda’s recent ex, Jesse, is scrutinized due to jealousy and suspicious text message deletions. However, alibi and shoe evidence clear him ([25:55]–[31:18]).
  • Friend/colleague Mercedes Benz is observed at the scene but is cleared through surveillance footage ([33:25]–[35:40]).

Forensic Evidence & Lingering Mystery

• Physical Clues

  • “The most important piece of evidence found at the crime scene: a bloody sneaker print.” – Narrator ([21:17])
  • Palm print on a broken window and blood under Amanda’s fingernails (DNA).

• Stalled Case & Desperate Measures

  • With no clear suspects or DNA matches, the case stagnates. Michelle campaigns tirelessly, putting up a billboard, holding memorials, balloon releases, and keeping Amanda’s case in the public eye ([38:00], [38:14]).
  • The investigation is further shaken by a scandal: two police officers take and share unauthorized crime scene photos, prompting a lawsuit and lasting trauma for Amanda’s family ([44:55]–[46:25]).

Breakthrough: A Name in Plain Sight

• Hidden Clue on a Whiteboard
  • More than two years later, police review photos and spot “Dennis was waz here” written on a whiteboard in Amanda’s bedroom—a name no one in Amanda’s orbit recognizes ([47:45]–[48:47]).
  • Cell phone records connect Amanda to Dennis Rosa Roman, previously unknown to police except for a prior unrelated arrest.

The Confrontation & Interrogation of Dennis Rosa Roman

• Dennis’s Story Unravels

  • Initially, Dennis denies knowing Amanda or visiting her apartment but is cornered as the evidence (phone records, DNA, shoe size, palm print) mounts ([53:53]–[57:43]).
  • At first, claims he only sold Amanda marijuana, then admits to being in her apartment, later insists he merely witnessed the crime and tried to save Amanda, shifting his story with each new fact pressed by police ([64:05]–[66:41]).

• DNA Confirms the Killer

  • “The DNA that was found under her fingernails connects you to her. You know what? It doesn't just get there.” – Detective Ronald Gibbons ([65:58])
  • Dennis’s Air Max shoe also matches the bloody print at the scene.

• Motive Remains Unclear

  • Dennis never admits guilt—final story is that he intervened in a struggle started by another man, but never supplies a name or evidence for this claim ([66:16], [72:19]).
  • Police theorize a possible motive: Dennis intended to steal marijuana from Amanda’s apartment, and Amanda became a victim of circumstance ([76:51]).

Trial & Aftermath

• Prosecution’s Case

  • Prosecutors bring together converging forensic evidence and Dennis’s changing stories ([71:04]–[71:54]).
  • Defense tries unsuccessfully to argue Dennis was a bystander to another’s violence.

• Verdict & Sentencing

  • Jury finds Dennis Rosa Roman guilty of first-degree murder after five hours’ deliberation ([75:13]–[75:20]).
  • Michelle and family speak of profound relief, but also the persistent ache—true justice feels elusive since Amanda is gone ([75:46], [78:14]).

• Legacy and Reforms

  • Michelle’s lawsuit leads to a $110,000 settlement for the crime scene photo scandal; she also lobbies for and helps pass “Amanda’s Law,” banning unauthorized photos by first responders ([78:47]).
  • Michelle dedicates herself to victim advocacy and keeping Amanda’s story alive ([79:14]).

• Ongoing Legal Uncertainty

  • Due to changes in Massachusetts law regarding juvenile sentencing, Dennis (convicted at age 20) could be eligible for parole as early as 2028—Amanda’s family vows to contest this ([80:41]–[80:55]).

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Notable Quotes & Memorable Moments (with Timestamps)

• On the Pain of Loss

  • “Not knowing how to even comprehend what had happened, but then still knowing that, okay, I need to put my child to rest.”
    — Michelle Penna (Amanda’s mother), [01:17], [08:39]

• Community Suspicion

  • “Every single person in her life was a suspect. Everybody.”
    — Amy Lee (Amanda’s sister), [01:33]

• The Turning Point—‘Dennis was here’

  • “On the whiteboard, there was wording in it. Dennis was waz here.”
    — Detective Ronald Gibbons, [41:16], [47:57]

• The Breakthrough

  • “The DNA that was found under her fingernails connects you to her.”
    — Detective Ronald Gibbons, [65:58]

• Justice, Yet Incomplete

  • “Justice will never be served because she’s dead and he’s not.”
    — Michelle Penna (Amanda’s mother), [78:14]

• Strength & Advocacy

  • “Do you feel like she’s with you now?” — Narrator
    — “Oh, absolutely. All the time.”
    — Michelle Penna, [80:19]

• Amanda’s Motto & Legacy

  • “Keep your face to the sun. Never look back at your shadows. Just like her precious sunflowers.”
    — Michelle Penna, [80:27]

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Key Segment Timestamps

| Timestamp | Segment Description | |------------|------------------------------------------------------------------------| | 04:37 | Seth Green’s 911 call, discovery of Amanda’s body | | 10:01 | Police begin to suspect Amanda’s boyfriend, Seth | | 21:17 | Bloody sneaker print evidence discovered | | 23:24 | Seth cleared as a suspect | | 31:18 | Jesse (ex-boyfriend) cleared | | 39:05 | Hoax confession, case stalls | | 44:55 | Police officers’ crime scene photos scandal surfaces | | 47:45 | Whiteboard clue "Dennis was here" discovered | | 53:53 | Detective Gibbons confronts Dennis Rosa Roman | | 65:58 | DNA matches Dennis to scene | | 75:13–20 | Jury returns guilty verdict | | 78:47 | “Amanda’s Law” passed | | 80:27 | Michelle Penna’s message about Amanda’s enduring legacy |

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Conclusion

“What the Killer Left Behind” weaves a devastating portrait of loss and dogged perseverance. The episode stands as a testament to familial love, the power of forensic evidence, and the real-world consequences of persistence in the fight for justice. While Amanda’s murderer has been brought to justice, her family continues to grapple with lingering questions and the impact of her loss—ensuring that Amanda’s light continues to shine, and her story warns and inspires others.

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Transcript

[Narrator]

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[Michelle Penna (Amanda's Mother)]

But if you've forgotten to get that.

[Narrator]

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[Michelle Penna (Amanda's Mother)]

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[Seth Green (Amanda's Boyfriend)]

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[Michelle Penna (Amanda's Mother)]

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[Seth Green (Amanda's Boyfriend)]

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[Narrator]

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[Seth Green (Amanda's Boyfriend)]

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[Michelle Penna (Amanda's Mother)]

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[Detective Ronald Gibbons]

It was almost like Amanda talking from the grave. Is it a crime of passion? Is it a crime of revenge? What's going on?

[Narrator]

When you walk in this apartment, you see Amanda Plass lying there on the floor.

[Detective Ronald Gibbons]

She spread out on her back and there's blood all around her.

[Seth Green (Amanda's Boyfriend)]

There is no doubt that she was already dead. It wasn't even like she needs help. It was, she's dead, my worst enemy. I wouldn't want to have to go through that. It's just horrible.

[Michelle Penna (Amanda's Mother)]

Not knowing how to even comprehend what had happened. But then still knowing that, okay, I need to put my child to rest.

[Amanda's Sister Amy Lee / Friends]

Every single person in her life was a suspect. Everybody.

[Seth Green (Amanda's Boyfriend)]

She said she had a lot of bad relationships in the past.

[Dennis Rosa Roman (Accused)]

Oh my God.

[Michelle Penna (Amanda's Mother)]

You know what? Mom ain't playing around no more. Somebody knew something.

[Narrator]

Our story begins here in Chicopee, Massachusetts. A small city nestled alongside the Connecticut River. Chicopee is a suburb of Springfield, mass. It's about 90 miles outside of Boston. Here on bustling Memorial Drive is this busy Friendly's restaurant. It's a place for ice cream celebrations and familiar faces. One of Those familiar faces, 20 year old Amanda Plass. More than a waitress really. Those who knew her said she was the heart of this place.

[Amanda's Sister Amy Lee / Friends]

Amanda really connected with the customers there.

[Michelle Penna (Amanda's Mother)]

She had a child that used to come in and only liked red gummy bears on a sundae. So she made his sundae with just the red gummy bears. That's just how Amanda was. Everybody loved her.

[Amanda's Sister Amy Lee / Friends]

We would come here and we would ask for her because she just brightened our day. She was just a sweetheart.

[Narrator]

It was a warm evening in August, right around 5:00. And Malene Holmes sat right here in this friendlies waiting for Amanda. Malene was a customer and she and Amanda had become friends. They were supposed to meet right before Amanda's shift for dinner.

[Amanda's Sister Amy Lee / Friends]

She used to come here and have dinner with us before she'd start her shift. We had been waiting for her and then she didn't show. Everybody was concerned. They were trying to call her and there was no response. Everybody was like, where is she?

[Michelle Penna (Amanda's Mother)]

It was just very strange.

[Amanda's Sister Amy Lee / Friends]

It was very, very strange.

[Narrator]

Even more strange was when minutes turned to hours and the ever reliable Amanda Plass never arrived for her shift at Friendliest. Not long after Amanda fails to show up for work, a frantic 911 call comes into the Chicopee Police Department. The caller is a 22 year old named Seth Green. And Seth tells dispatchers that when he went to visit his girlfriend Amanda, he stepped into a scene of unimaginable horror.

[Seth Green (Amanda's Boyfriend)]

She was, she was laying on the kitchen floor right when I opened the door, just in a pool of blood, stabbed to death. Called 911. I didn't, I was still holding her. When I called 911, there was no doubt that she was already dead. It wasn't even like, she needs help. It was, she's dead. She was slit, throat was slit, you know, multiple stab wounds to the chest, right in the heart.

[Detective Ronald Gibbons]

I was the on call state police detective for that particular day. I got a call to say that there was a homicide occurred in Chicopee.

[Narrator]

Ronald Gibbons, who at the time was a detective with the Massachusetts State Police, raced to the crime scene. What's the scene like? You arrive, what are you taking in?

[Detective Ronald Gibbons]

This is the building itself. The Chickau Bay police officers had caught on off this area, had put the yellow tape around it, right, to block anyone from going to the back.

[Narrator]

When the first detectives arrived at the scene, Lt. Gibbons says Seth was in distress and sitting on the back porch.

[Detective Ronald Gibbons]

He was frantic, he was erratic, he was just a range of emotions.

[Narrator]

What was that like for you to see her on that floor?

[Seth Green (Amanda's Boyfriend)]

It's just something that I would never wish upon anybody, like, you know, my worst enemy. I wouldn't want to have to go through that. Honestly, it's just horrible.

[Narrator]

When you walk in this apartment, you see Amanda Plass lying there on the floor. Describe the position she was in and what you're taking in as you see her.

[Detective Ronald Gibbons]

She's like spread out on her back and there's blood all around her.

[Michelle Penna (Amanda's Mother)]

Death by stabbing is very often a personal attack on behalf of the perpetrator. You have to be up on top of somebody when you plunge that knife into them.

[Detective Ronald Gibbons]

It was almost like Amanda talking from the grave. Is it a crime of passion? Is it a crime of revenge? There's a lot of slashes here. This was very violent. It Looked like she fought.

[Seth Green (Amanda's Boyfriend)]

I knelt down right next to her. I wanted to, you know, imagine or think that she was breathing or something. And I literally. I tried to give her cpr, like blow into her mouth, and it literally blew out of her. She was pretty butchered up. And, yeah, it's just horrible.

[Michelle Penna (Amanda's Mother)]

She's lying on the floor in a pool of blood with multiple wounds, partially dressed and very dead.

[Narrator]

It's around the same time that Amander's sister, Amy Lee, receives an unexpected visit from her aunt.

[Amanda's Sister Amy Lee / Friends]

And she told me, you know, your sister's dead. Your sister's been murdered. And I remember just crying instantly. I remember screaming. And my aunt is like, we need to find out who did this. We need to find out right now. And as we're en route to go tell her, my mom's calling me and she's saying, amy, what's going on? My mom's begging me to tell her on the phone, what's wrong?

[Michelle Penna (Amanda's Mother)]

So I went outside and there were the chickabee detectives and the state, my daughter, my husband, to let me know that she had been stalked, stabbed to death.

[Narrator]

So in real time, you're learning that your daughter was stabbed to death. How difficult is it to process all of this that's going on in that moment?

[Michelle Penna (Amanda's Mother)]

Oh, my gosh, how am I going to bury this kid or What? You know, 19, 20 year old, has a. Has a life insurance policy. Where do you get the money? Just that whole process of not knowing how to even comprehend what had happened, but then still knowing that, okay, I need. I need to put my child to rest.

[Narrator]

It's something you can never be prepared for.

[Michelle Penna (Amanda's Mother)]

No, never in a million years.

[Amanda's Sister Amy Lee / Friends]

You see your friend and they're happy, they're vibrant, they're excited for life. And then all of a sudden, they're gone. And it just didn't make sense.

[Michelle Penna (Amanda's Mother)]

It still doesn't make sense.

[Amanda's Sister Amy Lee / Friends]

I had this heavy gut feeling that something. Something really bad was going to happen to Amanda. I was like, oh, my God, did I manifest this? Like, did I put that thought out.

[Dennis Rosa Roman (Accused)]

There.

[Amanda's Sister Amy Lee / Friends]

And it came true.

[Michelle Penna (Amanda's Mother)]

Nobody could understand why it happened because Amanda was just friends with everybody. I don't remember Amanda having any enemies.

[Amanda's Sister Amy Lee / Friends]

Every single person in her life was a suspect. Everybody.

[Michelle Penna (Amanda's Mother)]

Any detective or criminologist is gonna tell you that our money is on Seth Green, the most recent boyfriend.

[Detective Ronald Gibbons]

My captain is now saying, head to the station. They got a possible suspect. He's down at the station. They're going to interview him. Need you there right now. It's a race against Time.

[Seth Green (Amanda's Boyfriend)]

I think my knife may have been at her house.

[Detective Ronald Gibbons]

So you have a knife at our house? That knife was not found. Seth was a perfect suspect.

[Narrator]

To truly understand Amanda Plass, all you needed to do was look into her eyes.

[Michelle Penna (Amanda's Mother)]

She can see her soul, the love that she had for everybody and anybody.

[Amanda's Sister Amy Lee / Friends]

Her eyes changed colors when she was really happy. Her eyes would literally turn green.

[Narrator]

What stands out to you when you think about her?

[Michelle Penna (Amanda's Mother)]

Her spirit.

[Amanda's Sister Amy Lee / Friends]

Yeah. Her energy.

[Narrator]

Amanda grew up in Chicopee, once a bustling mill town, now a quiet working class community known for the rambling Chicopee River.

[Michelle Penna (Amanda's Mother)]

Chicopee is a small place. Everybody knows everybody.

[Detective Ronald Gibbons]

The neighborhood itself is a very close knit neighborhood. The houses are pretty adjacent to each other. Very urban residential neighborhood.

[Narrator]

How often does it happen that you have a random murder?

[Detective Ronald Gibbons]

A lot of times you have a gang murder. And this was different because this is truly a victim. In her own apartment, a young girl, 20 years old, brutally murdered.

[Narrator]

Amanda was the middle child raised by her mom, Michelle. She attended a local high school, but left before graduating and instead earned her ged.

[Michelle Penna (Amanda's Mother)]

She was a hippie child. I often find her barefooted outside painting or taking pictures of the neighbor's dog playing her guitar.

[Amanda's Sister Amy Lee / Friends]

Growing up, we were like best friends. My mom used to dress us up like we were twins. My mom was a single mother for most of our childhood and we moved around a lot.

[Michelle Penna (Amanda's Mother)]

I've always raised my children to be, you know, independent and you get what you earn.

[Amanda's Sister Amy Lee / Friends]

I used to call Amanda the bigger sister. She had a job, an apartment. Her work ethic was nonstop. Amanda was always dancing around and painting and splashing colors everywhere.

[Michelle Penna (Amanda's Mother)]

Anything that had to do with being artsy, she would make feather earrings.

[Amanda's Sister Amy Lee / Friends]

When you see a sunflower, you think of Amanda. It became her trademark when she found the music festival scene. That really is where she started to blossom. She's in her early 20s and she just found herself right before she passed.

[Michelle Penna (Amanda's Mother)]

A butterfly coming out of a cocoon. Just the brightness that was her.

[Narrator]

On that tragic Friday in Chicopee, Amanda's boyfriend Seth, whom she had only been dating for about a week, tells police he stopped by Amanda's apartment and immediately noticed a broken window.

[Seth Green (Amanda's Boyfriend)]

Pounded on the door for a minute.

[Dennis Rosa Roman (Accused)]

And then you try going to her apartment door.

[Seth Green (Amanda's Boyfriend)]

Yeah. Turn the handle on the hots. I went to her door and let myself in and she was laid on the floor in a pool of blood. She got up immediately and called. You have the right to remain silent. Do you understand that?

[Detective Ronald Gibbons]

Seth had only been dating Amanda for.

[Michelle Penna (Amanda's Mother)]

The week, but he said he had Moved his things in and it was a serious relationship.

[Seth Green (Amanda's Boyfriend)]

I've been hanging out every single day for a week now.

[Narrator]

And the relationship was moving fast, right?

[Seth Green (Amanda's Boyfriend)]

Yeah, it was moving fast. You know, she had that go getter attitude and just a fun, caring person.

[Narrator]

What were you doing for a living at the time?

[Seth Green (Amanda's Boyfriend)]

I'm a carpenter, but roofing is where the money's at. So roofing was my main go to usually for the construction field.

[Narrator]

Seth tells police he spent the night at Amanda's, left for work around 9am and returned to find her dead. He also tells investigators he was working on a roof that day and left the job site multiple times to purchase supplies.

[Seth Green (Amanda's Boyfriend)]

What time did you leave to get the materials? They had left like three times. It was later in the day, three to four.

[Amanda's Sister Amy Lee / Friends]

Like three to four of them.

[Narrator]

Seth says he and Amanda had kind of fallen into a routine. Every day after he finished working, Seth would drive Amanda to her job at Friendly's. However, the day she was murdered, Seth tells detectives that routine was broken because he had to work late.

[Detective Ronald Gibbons]

He was there every day that week to take her to work, but this is the one day that he had to work late. That kind of was suspicious to us.

[Narrator]

How important was Seth's timeline?

[Detective Ronald Gibbons]

His timeline is very important. He leaves the job site several times and he's on his own. So where exactly did he go or what exactly did he do?

[Seth Green (Amanda's Boyfriend)]

I text her, I said, where are you? She didn't answer. My first thought was like, oh, she just. She stayed home. Maybe she couldn't find a ride.

[Narrator]

So you weren't like, concerned or anything at that point?

[Seth Green (Amanda's Boyfriend)]

No, not at all. I drove her straight to her house, expecting to see her there waiting for.

[Dennis Rosa Roman (Accused)]

Me, you know, oh, my God.

[Seth Green (Amanda's Boyfriend)]

She deserves so much. You give it all to her.

[Detective Ronald Gibbons]

These range of motions does not add up. He's rising to the occasion of being a suspect.

[Michelle Penna (Amanda's Mother)]

The interrogators zone in immediately on the fact that Seth Green is a carpenter and a roofer. In other words, he uses sharp objects and utility knives all the time.

[Narrator]

Then comes a chilling detail that ratchets up the suspicion on Seth. He tells detectives the knife he used at work, sharp m Tech blade, has gone missing.

[Seth Green (Amanda's Boyfriend)]

I think my knife might have been at her house.

[Detective Ronald Gibbons]

So you have a knife at our house?

[Seth Green (Amanda's Boyfriend)]

Yeah, I think it might be at her house.

[Dennis Rosa Roman (Accused)]

It might be in my car as well.

[Seth Green (Amanda's Boyfriend)]

I'm not sure.

[Detective Ronald Gibbons]

He was missing his M. Tech knife that he didn't take to work that day. That knife was not found. Sef was the perfect suspect.

[Seth Green (Amanda's Boyfriend)]

My Girlfriend just got murdered and you're blaming me for it? Dude, are you kidding me?

[Narrator]

And now police want to know if a telltale piece of evidence left behind at the crime scene will implicate or exonerate Seth Green. Michelle Penna will never forget the final text message she received from her daughter Amanda.

[Michelle Penna (Amanda's Mother)]

She sent me a text and said, mom, can you give me a ride to work? And I said, I can't. And she said, okay, she'd find a ride.

[Narrator]

No one could have imagined that just hours later, 20 year old Amanda Plass would be gone forever.

[Amanda's Sister Amy Lee / Friends]

Homicides happen all the time, but when it happens to you, I would have never thought that my sister was going to be murdered.

[Narrator]

What you stumbled upon when you went to Amanda's house, how does that compare to a lot of other homicides you've covered?

[Detective Ronald Gibbons]

In this particular case, there's droplets of blood all around the room. And that's indicative, though this was a very, very brutal and harsh fight.

[Michelle Penna (Amanda's Mother)]

Well, when we were finally able to get into her apartment, they had covered the floor with paper so we didn't have to see all the blood. So when you're trying to clean out her apartment, as I'm walking across paper to cover my daughter's bladder blood, and then who do you ask to help?

[Detective Ronald Gibbons]

My theory is that the attacker came through the back door when he found Amanda. She's actually in her work pants, her work clothes. There was no evidence of a sexual assault.

[Michelle Penna (Amanda's Mother)]

She was found on the kitchen floor, and they do believe she was killed there. So not in a bedroom, not in the living room. And that suggests perhaps an element of surprise.

[Detective Ronald Gibbons]

She just didn't lay down and die. She actually fought back. And when she fought back, underneath her fingernails was possibly DNA. And we were going to have to match this DNA to someone.

[Narrator]

The first person investigators test, Amanda's boyfriend, Seth Green.

[Michelle Penna (Amanda's Mother)]

I'm going to do a couple tests.

[Amanda's Sister Amy Lee / Friends]

We're just going to swipe the inside of your cheek.

[Detective Ronald Gibbons]

Okay? The interesting thing, we stepped out of the room, but we still observed him. And he'd cry a little bit and then just wonder why he was there.

[Seth Green (Amanda's Boyfriend)]

I can't believe that. So happy with her.

[Michelle Penna (Amanda's Mother)]

What happened?

[Detective Ronald Gibbons]

He had only been dating her for a week, and he was so caught up that this is the best thing that ever happened to his life.

[Narrator]

But detectives also receive information that points to someone other than Seth. Amanda had recently told her family that someone had been sneaking into her apartment.

[Michelle Penna (Amanda's Mother)]

She said, my apartment got broken into again. And I said, well, what did they take? You need to call the police. And she says, no, mom. All they took was a. Was a glass bowl, like a marijuana bowl. I said, well, you still need to call the police. And she said, no, what am I going to do? Tell them I. My pot got stolen?

[Narrator]

Amanda's friends say she suspected an unidentified male was watching her.

[Detective Ronald Gibbons]

She saw him peeking into her back window at her apartment. The window is actually broken. And we surmised that the person possibly had tried to make it look like a break in. So on that same window, you end up with a palm print. We can identify the palm print. We can also identify the person that would have been there that particular day.

[Narrator]

But among the most important piece of evidence found at the crime scene, a bloody sneaker print.

[Detective Ronald Gibbons]

That footprint showed a sneaker print in blood. You can actually see the Nike impression in that footprint. We had it measured, we had it analyzed. That was very important because a smaller shoe, maybe a female, maybe a male. We were looking for a Nike size 7 and a half Air Max shoe.

[Michelle Penna (Amanda's Mother)]

I remember a couple days after she was murdered, everybody had, like, went to her apartment in Chicopee center and just held, like, a memorial. The whole front of her building was just a sea of sunflowers.

[Amanda's Sister Amy Lee / Friends]

That was a really intense emotional time to be in front of the apartment of where she was murdered and just comforting each other. Just shocked, not understanding how or why.

[Narrator]

And then a few days after Amanda's murder, there was a funeral.

[Amanda's Sister Amy Lee / Friends]

I just remember it just being beautiful and intense and very heartbreaking and a lot of sunflowers.

[Narrator]

Meanwhile, police aren't giving up on the idea of Amanda's boyfriend Seth as a suspect. Within hours of Amanda's murder, they even go as far as to ask him for the shoes on his feet.

[Detective Ronald Gibbons]

Would you give us permission to look at your shoes?

[Narrator]

Yeah, you can take them.

[Seth Green (Amanda's Boyfriend)]

Let me take them off now.

[Detective Ronald Gibbons]

Just put up.

[Narrator]

Finally, after almost 15 grueling hours, investigators reach a conclusion. Seth Green is not their killer.

[Detective Ronald Gibbons]

His DNA did not match. His shoe print didn't match. His boots were a size 12. It was too large to be the person at the scene.

[Seth Green (Amanda's Boyfriend)]

Clearly, there's some other shoes there that were not mine. And that's the thing that got me released.

[Narrator]

Honestly, what did that moment feel like for you?

[Seth Green (Amanda's Boyfriend)]

Well, it's definitely a big relief, you know, honestly. Yeah. When they were walking me out was definitely an in awe moment. Like, you know, finally, like I told you guys a million times, it wasn't me.

[Narrator]

What is that like to go through that, to experience the loss and then to have to face that questioning?

[Seth Green (Amanda's Boyfriend)]

I Mean, it's unbearable, honestly, it's like, I just called you guys, like, you know, why are you trying to blame me for this? Like, you know, I like, I love this girl.

[Narrator]

Seth is officially cleared as a suspect and tells cops there's someone else they should be looking at.

[Seth Green (Amanda's Boyfriend)]

She said she had a lot of bad relationships in the past.

[Narrator]

Detectives also want to learn about an ex boyfriend who was allegedly upset after seeing a public display of affection between Seth and Amanda at friendlies while she was working.

[Detective Ronald Gibbons]

He had showed up at work, and they start making out.

[Narrator]

And detectives say that ex's reaction wasn't very friendly at all. So at the very least, you had to consider that he could have had something to do with this.

[Detective Ronald Gibbons]

Very much so. A motive of revenge is in our mind.

[Narrator]

What surprised you most about the conversations police were having with you?

[Seth Green (Amanda's Boyfriend)]

It was hard for me to hear them. Kind of making me feel like they're, you know, asking me questions like if I. As if I were the one that did it. Not something I'd ever want anyone to have to go through. It's just horrible.

[Detective Ronald Gibbons]

Any problems last night at all?

[Seth Green (Amanda's Boyfriend)]

So happy since red sweat. She said she had a lot of bad relationships in the past.

[Narrator]

Amanda's boyfriend, Seth Green, is fully cleared. But now investigators wonder if one of those previous relationships could be a factor in Amanda's murder. They discovered that before Seth, Amanda had been seeing a man named Jesse.

[Detective Ronald Gibbons]

He was a boyfriend of Amanda, basically a week before Seth was. And he also worked at Friendley's.

[Narrator]

So at the very least, you had to consider that he could have had something to do with this.

[Detective Ronald Gibbons]

Very much so. Jesse wanted a serious relationship. Amanda didn't, and she finds a new boyfriend.

[Narrator]

Police learn of an alleged incident at Friendly's involving Jesse and Amanda's new boyfriend Seth. That raises alarm bells for authorities.

[Detective Ronald Gibbons]

Friday was a murder. Thursday night, when Jesse's working, Seth shows up at the Friendly's.

[Narrator]

Amanda's boss at Friendly's tells police Seth came in and kissed Amanda openly. Jesse saw it, and he looked uncomfortable. Afterwards, Jesse asked to go home.

[Detective Ronald Gibbons]

A little later, Jesse moves up the chain as a very likely suspect. A motive of revenge is in our mind about Jesse.

[Narrator]

I want to play some of your interrogation from speaking to Jesse.

[Detective Ronald Gibbons]

So you both worked at Friendly's on that Thursday, right?

[Dennis Rosa Roman (Accused)]

Correct.

[Detective Ronald Gibbons]

You left work early, right?

[Narrator]

Correct. You told us you left because they.

[Seth Green (Amanda's Boyfriend)]

Over scheduled you, right?

[Narrator]

Yeah.

[Seth Green (Amanda's Boyfriend)]

Okay, well, that's not what we heard. We heard that Seth went in there, gave her a kiss that made you want to kiss him for, like, A while.

[Narrator]

And he did kiss.

[Seth Green (Amanda's Boyfriend)]

He did kiss a man in front of you, and it made you. I thought I seen. Seen them talking. It didn't bother me. I was talking to Seth, but I never physically seen them because not once.

[Detective Ronald Gibbons]

You knew that Amanda was dating Seth?

[Amanda's Sister Amy Lee / Friends]

Yeah.

[Dennis Rosa Roman (Accused)]

How'd that make you feel?

[Seth Green (Amanda's Boyfriend)]

It sucked. But what are you gonna do?

[Narrator]

After he left work, Jesse says he texted Amanda about some items they wanted back from each other now that their relationship was. Was over. But investigators press him about the nature of those messages.

[Detective Ronald Gibbons]

Was there any anger in a text?

[Seth Green (Amanda's Boyfriend)]

Not in that text. I don't believe so.

[Detective Ronald Gibbons]

But there was some anger in some other texts, weren't they?

[Seth Green (Amanda's Boyfriend)]

Yeah. I was just angry at the fact that she just didn't talk to me for a few days, and I was just wondering what was going on. I was just pissed that she wouldn't tell me.

[Detective Ronald Gibbons]

And this is the time that she's now with Seth.

[Seth Green (Amanda's Boyfriend)]

I don't know if I knew about it, but she's probably talking to him then.

[Narrator]

At this point, you're trying to figure out who might have been involved. How does this information fit into your investigation?

[Detective Ronald Gibbons]

We're looking at the fact of who could have done this, who was angry at her? Because as we look at the scene, there's a lot of blood. There's a lot of anger going on. It's not a one and done out the door. Can we also look at your phone?

[Seth Green (Amanda's Boyfriend)]

What'd you do with those text messages that you texted her?

[Detective Ronald Gibbons]

Did you delete them?

[Seth Green (Amanda's Boyfriend)]

All my texts are delete.

[Detective Ronald Gibbons]

Because you felt they were uncomfortable?

[Seth Green (Amanda's Boyfriend)]

First of all, I didn't want to look at any conversation of me and her just because it made me sad to even think about her. Why is that? Because she's murdered. So you deleted them after you found out she was killed? I didn't even want to have to look at them. Everything reminds me of as an investigator.

[Narrator]

What do you make of that?

[Detective Ronald Gibbons]

He's trying to hide something, so now there's obviously texts say he doesn't want investigators to see. Did he delete him because she's dead, or is he part of something that happened to her?

[Narrator]

Deleting text messages certainly seems out of the ordinary.

[Detective Ronald Gibbons]

Yes, it does.

[Narrator]

Now investigators want to know if Jesse was doing anything out of the ordinary. The day of Amanda's murder, did you.

[Detective Ronald Gibbons]

Stay home all day?

[Seth Green (Amanda's Boyfriend)]

Most of the day. The only time I really left was to go to Friendly's.

[Detective Ronald Gibbons]

What did you go there for?

[Seth Green (Amanda's Boyfriend)]

For my check.

[Narrator]

Did you cash it?

[Seth Green (Amanda's Boyfriend)]

No. Oh, actually, yeah, I did. Cash it at General's. How did you get there? I got a ride.

[Detective Ronald Gibbons]

From who?

[Seth Green (Amanda's Boyfriend)]

Kyle.

[Detective Ronald Gibbons]

He says he goes to Jen rows. We check a tape to verify his story. We learned that Kyle did not drive him there. So Jesse had lied. Jesse, we interviewed you to twice already. And were you telling us the truth?

[Seth Green (Amanda's Boyfriend)]

Everything except for about me taking my car to General. Why? Why weren't you telling the truth about that? Cuz I told you guys that I didn't drive my car. And then when we got in the story, I remembered I took my car to General. I just didn't want to go back. My word. I was scared. I don't know. I regretted it the second.

[Dennis Rosa Roman (Accused)]

You were scared? Yeah.

[Seth Green (Amanda's Boyfriend)]

What were you scared about? Just nervous. I've never been interrogated before or anything like that. Never had to deal with anything like this.

[Detective Ronald Gibbons]

Basically his story is he didn't want to tell his parents he wasn't supposed to be driving. So he's more afraid of his parents than he was of the police. Jesse has lied about who is with from friendlies. Quite possibly if he's in the car by himself, he could have went by Amanda's and then went to Jenros.

[Narrator]

With questions lingering over Jesse's account, investigators decide to compare his shoes to the bloody shoe prints left at the crime scene.

[Detective Ronald Gibbons]

No, look at those vans.

[Seth Green (Amanda's Boyfriend)]

Yeah, I have like two pairs of these. Let's see when I went to the bottom.

[Narrator]

Yeah.

[Detective Ronald Gibbons]

The other side.

[Narrator]

Ultimately, Jesse's shoes are not a match and his alibi checks out.

[Detective Ronald Gibbons]

We talk to people at General's. He's not bloody. He's cashing his check.

[Narrator]

Those close to Jesse never thought for a second that he was capable of such a heinous crime. Tell me about Jesse.

[Michelle Penna (Amanda's Mother)]

Jesse's a great kid.

[Amanda's Sister Amy Lee / Friends]

When his name was brought up, that was a absolutely not moment. I've never seen Jesse angry. Sweetest, sweetest kid. And I know that was really intense for Jesse. Yeah, I know that was. You know, to be put in that spotlight and to have the whispers, I think that was really hard for him.

[Narrator]

With Jesse now fully cleared by authorities, investigators follow another lead. A mysterious vehicle that a witness says she saw speeding away from Amanda's apartment right around the time of the murder.

[Detective Ronald Gibbons]

So to us it's like, wow, that's, that's big. We're on the lookout for a white.

[Narrator]

Sedan and a 911 call comes in that might just turn the entire case on its head.

[Dennis Rosa Roman (Accused)]

Police court of my dispatch daily speeding. I'd like to call and turn myself in. Best know what you're turning yourself in for a murder.

[Seth Green (Amanda's Boyfriend)]

Jesse, there's a couple things that are.

[Narrator]

Bothering me here on your statements. Amanda's ex boyfriend, Jesse, raised eyebrows when detectives say he was less than forthcoming with information.

[Seth Green (Amanda's Boyfriend)]

You said you still don't know how she died. I don't. You don't? I find that very hard to believe that you have no idea how she died when everybody's talking about it. It's been on the news.

[Narrator]

But after determining Jesse had a solid alibi, he was cleared and investigated. Investigators with the Chicopee police and the state police quickly move on. Still unclear who exactly they're searching for.

[Michelle Penna (Amanda's Mother)]

One of the best clues that investigators find is a shoe print, a sneaker that is a size 7 and a half men's shoe, which is very small for men. It's the smallest size you can get in men's shoes. Or it could be a woman size nine.

[Narrator]

Investigators get a new lead from a neighbor of Amanda, a witness who told police she saw a suspicious car the day of the murder outside Amanda's apartment. And so afterwards, as you're learning more about the scene, you learn about this white sedan that's here that peels away.

[Detective Ronald Gibbons]

At one point, Right?

[Narrator]

Not a common thing to do.

[Detective Ronald Gibbons]

Not a common thing to do. And we actually got that information from the neighbor next door. They remember a white car here, and they just remember a female, single female in the car pulling away at a high rate of speed around the 4:30 hour. And then we identify who that white car was. Ended up being a girl from EAS Hampton named Mercedes Benz.

[Narrator]

That's right. Her name is Mercedes Benz. Another friend of Amanda's who works at Friendly's.

[Amanda's Sister Amy Lee / Friends]

Mercedes was a really nice girl. She was a waitress here also, and she was friends with Amanda, and we used to talk to her all the time also.

[Narrator]

Now it was police who wanted to talk to Mercedes Benz. Mercedes tells detectives that Amanda had texted her earlier that day asking for a ride to work. She said it was a little after 5pm when she arrived at Amanda's building. This is right around the time when police believed Amanda was murdered. Mercedes said she called and texted Amanda to let her know that she'd arrived. But after waiting five or six minutes, she said she left.

[Detective Ronald Gibbons]

We talked to Mercedes Benz, and she says, well, the reason I had to leave was I had to go to Walmart.

[Narrator]

Does that add up for you?

[Detective Ronald Gibbons]

It doesn't add up because her purpose of coming here all the way from East Hampton was to give a ride to Amanda to work to Friendly's, which is basically five to ten minutes down the road. So it doesn't make sense if you pull up here to get her, why would you just leave without even going upstairs?

[Narrator]

But what seems like a promising lead fizzles out. That neighbor who saw Mercedes speed away confirms she never got out of her car. And police obtained surveillance footage from Walmart that backs up her timeline. That's her in the white sedan pulling into Walmart. And more footage shows her shopping inside the store.

[Detective Ronald Gibbons]

Mercedes was basically cleared once we were able to get the tape from Walmart.

[Narrator]

Frustrated, investigators pushed forward now casting a very wide net.

[Michelle Penna (Amanda's Mother)]

I mean, they were taking DNA from everybody and anybody.

[Detective Ronald Gibbons]

We made a point for the medical examiner to make funeral clippings of her fingernails. On this particular case, it was entered in a database and there was no convictions for a felony that would have matched it.

[Narrator]

With no matches to the DNA collected at the crime scene and no viable suspects, the case stalls. What surprised you most about this time?

[Michelle Penna (Amanda's Mother)]

I think how tight lipped they were, whether it was Ronnie Gibbons or should be detectives. Nobody was talking, even to me. Nobody was talking. They were very tight lipped about certain things.

[Narrator]

How did that make you feel?

[Michelle Penna (Amanda's Mother)]

It was very frustrating at first because I wanted answers. And I would call every Sunday night. I would call down the Chickabee police department looking for the detectives. What's the update? What's the update? What's the update? Got nothing to tell you, Michelle. Got nothing to tell you, Michelle. But it's just, at what point is I never gave up, but you just think, is this gonna be a cold case? Will I ever know.

[Narrator]

That fear of never getting justice for Amanda was fuel for a fire that was now burning inside Michelle.

[Amanda's Sister Amy Lee / Friends]

My mom made it very clear that she wasn't just gonna let the case go cold.

[Michelle Penna (Amanda's Mother)]

I didn't give up hope because Michelle never gave up hope. She never gave up. She didn't let anybody else either.

[Narrator]

Tell me about how after this time had passed that you said, I gotta take matters into my own hands.

[Michelle Penna (Amanda's Mother)]

I was driving home from work and I saw a billboard. And underneath it was Lamar and company. And I said, you know what? Mom ain't playing around no more. I called them and emailed them, and next thing I knew, Amanda's billboard went up.

[Narrator]

And that's just the beginning, right?

[Michelle Penna (Amanda's Mother)]

You did flyers, balloon releases. I even had cards made up, business cards with the TexasTip number on it. We attached them to the balloons when we did the balloon releases. One of the balloons ended up three hours away. Cape Cod.

[Narrator]

Wow.

[Michelle Penna (Amanda's Mother)]

It's been 18 months and five days since Amanda was murdered. So today I'm hoping with the release of these balloons that somebody will come forward. Somebody knows something that happened that day. It was a busy Friday afternoon. We're just looking for that one missing piece of the puzzle.

[Amanda's Sister Amy Lee / Friends]

She was just in your face. She really was like you would be as a mother. We want to find out what happened to your child. And she was out there. She was going to find out. Michelle's a force.

[Narrator]

Despite Michelle's efforts to publicize Amanda's case, the investigation continues to languish. Then, a dramatic development. More than a year after the murder, a 911 call comes in that initially stuns police. A man confesses to Amanda's murder.

[Dennis Rosa Roman (Accused)]

I like to turn myself in. I live in Plymouth. Spell your last name. Do I really have to? I'm turning myself in.

[Detective Ronald Gibbons]

Right.

[Dennis Rosa Roman (Accused)]

But I have to know what you're turning yourself in for. A murder from where, sir? From Chicopee. Up from Amanda Platte. And I just can't handle it anymore.

[Narrator]

Cops track down the corner, but just like hundreds of other promising leads, the confession is a dead end. The caller was impersonating another man, trying to get him in trouble. Neither had any involvement in the murder.

[Detective Ronald Gibbons]

They had read it online, facts about the murder. And once you got through the facts, there was no factual basis to their. To the confession. This is a very frustrating investigation.

[Narrator]

And then a discovery that blows the investigation wide open.

[Detective Ronald Gibbons]

And I still remember the night, it was probably 10 o' clock at night.

[Michelle Penna (Amanda's Mother)]

I get a call from Ronnie Gibbons.

[Detective Ronald Gibbons]

Michelle, you got that whiteboard from the apartment?

[Narrator]

A clue that had been hiding in plain sight all along.

[Amanda's Sister Amy Lee / Friends]

I never heard his name.

[Narrator]

Had you ever heard of Amanda mention something? Nope. Dennis?

[Michelle Penna (Amanda's Mother)]

Never, not once.

[Narrator]

Can you spot the clue on this whiteboard.

[Dennis Rosa Roman (Accused)]

Where do you guys want me to start?

[Michelle Penna (Amanda's Mother)]

Nobody could wrap their head around the fact that Amanda was killed to begin with, let alone trying to think of.

[Amanda's Sister Amy Lee / Friends]

Who could do it. We had a billboard on 391, a huge billboard with this beautiful picture that she took of herself that day she was murdered.

[Michelle Penna (Amanda's Mother)]

Somebody knew something and nobody was talking.

[Amanda's Sister Amy Lee / Friends]

I kept saying, there's no way that there's no DNA. There's just no way. There has to be something.

[Detective Ronald Gibbons]

There was a whiteboard way in the back on a whiteboard. There was wording in it. Dennis was waz here.

[Michelle Penna (Amanda's Mother)]

Who's Dennis?

[Amanda's Sister Amy Lee / Friends]

I got goosebumps right now.

[Michelle Penna (Amanda's Mother)]

So I was on the way to the hospital. They had told me 12 hours before I had her that I was having a boy. And Amanda, by Boston was on the radio as her godmother. And I drove to the hospital, and when she was born, the nurse looked at me and said, it's not a boy. So I named her Amanda after the song by Boston.

[Dennis Rosa Roman (Accused)]

I'm gonna take you by surprise and.

[Narrator]

Make you realize Amanda, I love you.

[Michelle Penna (Amanda's Mother)]

She was just always bubbly and fun.

[Amanda's Sister Amy Lee / Friends]

And she had this big curly hair, and she just.

[Michelle Penna (Amanda's Mother)]

She was a light.

[Narrator]

But on that tragic Friday in August, Amanda's bright light was extinguished when she was found brutally murdered in her apartment.

[Seth Green (Amanda's Boyfriend)]

She was laying on the kitchen floor, right when I opened the door, she had pool of blood, stabbed to death.

[Detective Ronald Gibbons]

I got the call to say that we have a homicide in response to the scene. So I actually responded to the scene. Initially.

[Michelle Penna (Amanda's Mother)]

People in the neighborhood were worried, is someone going to come to my door and kill me? You don't even think it's real at first. You know, you're numb to it.

[Amanda's Sister Amy Lee / Friends]

Then you're like, okay, maybe something's like.

[Michelle Penna (Amanda's Mother)]

A miss, like, maybe this isn't true. Nobody could wrap their head around the fact that Amanda was killed to begin with, let alone trying to think of.

[Amanda's Sister Amy Lee / Friends]

Who could do it.

[Narrator]

At the crime scene, police discover a partial palm print on the broken bottom window and a bloody shoe print in the kitchen near Amanda's body. But with lead after lead coming up empty, the investigation is losing momentum.

[Michelle Penna (Amanda's Mother)]

They interview hundreds of people who knew her friends, relatives, co workers, and there is nothing new under the sun. Unless somebody comes forward with new information, this case is going to grow cold.

[Narrator]

I think there's this impression sometimes that a murder happens, police will solve it in months. Some cases, they take time, they linger. Was that frustrating for you?

[Detective Ronald Gibbons]

It was very frustrating. Very frustrating because, you know, as time goes on and you have to realize that in 2011, when this occurred, time didn't stop, investigations didn't stop. Crime didn't stop. So we were working other cases as well.

[Michelle Penna (Amanda's Mother)]

I was getting nervous that her case was going cold. Somebody knows something that happened that day. We're just looking for that one missing piece of the puzzle.

[Narrator]

Amanda's mother, Michelle, takes matters into her own hands, organizing benefits, balloon releases. She even got a massive billboard with Amanda's picture put up on the highway.

[Michelle Penna (Amanda's Mother)]

I wanted people driving down the highway and seeing my daughter's face. Somebody knew something, and nobody was talking.

[Narrator]

But then, a little more than a year after the murder, the story takes a strange turn. Rumors are swirling in Chicopee about graphic crime scene photos seen at a high school football game.

[Michelle Penna (Amanda's Mother)]

New details on the Chicopee police officers Accused of taking pictures of murder victim Amanda Plass's body. It was June 10th of 2013. I will never forget. There was a news conference. It was the then mayor who was appointing a new chief of police and said that they were investigating a crime scene photo leak by two of the Chicopee police officers.

[Amanda's Sister Amy Lee / Friends]

My heart just sank. What do you mean? Police officers were taking pictures of the crime scene and sharing them.

[Narrator]

Two Chicopee police officers who had been assigned to protect the crime scene took photos of Amanda's body with their personal phones. And adding insult to injury, they forwarded the pictures to other officers, and it was shown to coaches at a high school football game.

[Michelle Penna (Amanda's Mother)]

Everyone, the whole newsroom was, how could anyone do this? How could an officer do this?

[Narrator]

Michelle sued the police department and the city, claiming emotional abuse suffered at the hands of the chikaped.

[Michelle Penna (Amanda's Mother)]

They sued him for $10 million. I sued the city. The police department sued them all. It wasn't about the money. It was about proving a point.

[Narrator]

An internal affairs investigation called the behavior an affront to the professionalism otherwise demonstrated by Chicopee and the state investigators. In this case, the officers responsible were disciplined by the police department.

[Michelle Penna (Amanda's Mother)]

They were there to protect the scene. And at my daughter's most vulnerable moment, you disrespect her in the worst way ever and think that's okay. I just. Oh, I was mad.

[Narrator]

At the same time Michelle's dealing with the photo controversy, she's campaigning tirelessly to keep Amanda's murder case front and center. What was it like for you to have to handle questions about that controversy while at the same time, what you're really focused on is finding your daughter's killer.

[Michelle Penna (Amanda's Mother)]

Yeah. And I think that's the hard part of it all. I didn't want the controversy to overshadow the fact that. That we still did not have justice for Amanda. We were still looking and begging for that end to be closed.

[Narrator]

Investigators working on Amanda's case had no involvement in the alleged scandal. Frustrated by the lack of progress, they go back to square one, reviewing everything from scratch.

[Detective Ronald Gibbons]

We would try to keep saying, what do we miss? What do we miss? What do we miss?

[Narrator]

And then a breakthrough. While reviewing photos of the crime scene, investigators spot a potentially critical clue that had been overlooked hiding in plain sight in Amanda's bedroom.

[Detective Ronald Gibbons]

We come upon, in a scene where the table is at, there was a whiteboard way in the back. On the whiteboard, there was wording in it. Dennis was Waz here. 8, 11, 11.

[Narrator]

The grizzly murder took place in the kitchen. But the whiteboard was in Amanda's bedroom, which appeared undisturbed, and they missed the clue.

[Michelle Penna (Amanda's Mother)]

I get a call from Ronnie Gibbons, and it was like quarter to 10 at night.

[Detective Ronald Gibbons]

Michelle, you got that whiteboard from the apartment?

[Michelle Penna (Amanda's Mother)]

I said, yeah, it's in the closet. He said, I'll be over in five minutes. I gotta grab it.

[Narrator]

After more than two years, investigators finally had a name. But the answer to the question, who is Dennis? Only brings more mystery. This Dennis was here on this whiteboard. This is a huge clue for your case.

[Detective Ronald Gibbons]

This is a big clue.

[Narrator]

Why?

[Detective Ronald Gibbons]

Because Dennis name had never come up. The investigation.

[Michelle Penna (Amanda's Mother)]

Now we're scrolling through Amanda's Facebook going, who's done this?

[Detective Ronald Gibbons]

She didn't know. Amy Lay didn't know.

[Michelle Penna (Amanda's Mother)]

Her friends were calling me going, done it. Nobody knew who Dennis was.

[Narrator]

Amanda's friend Desiree said, through force of sheer will, you kept her name out there. How difficult was that?

[Michelle Penna (Amanda's Mother)]

It was difficult. It takes a toll. And there are some nights where you just, again, you don't want to be that mom. But then something else would pop up and you'd be like, okay, let me call Trooper Gibbons. It was tough. It was very tough.

[Detective Ronald Gibbons]

I had Michelle that was calling me at 11 o' clock at night, 12 o' clock at night, mad and angry. You got to do something. You got to do something.

[Michelle Penna (Amanda's Mother)]

There was never a time where Ronnie did not show up at my house without a smile on his face. The only side that I saw was the compassionate side, the side that said, I'm here to the end.

[Narrator]

It was a Wednesday night in October, more than two years after the murder, when Detective Gibbons was the one making a late night phone call to Michelle.

[Michelle Penna (Amanda's Mother)]

It was October 30, 2013. Quarter to 10 at night, I get a call from Ronnie Gibbons. Hey, you still got that whiteboard from Amanda's apartment? I said, yeah, it's in the closet. He said, I'll be over in five minutes. I gotta grab it.

[Narrator]

The discovery of a name hiding in plain sight on a whiteboard in Mana's apartment kickstarts an investigation that, frankly, had been on life support. Now the question everyone is asking, who's Dennis?

[Detective Ronald Gibbons]

Noah knew Dennis.

[Narrator]

Had you ever heard Amanda mention someone named Dennis?

[Michelle Penna (Amanda's Mother)]

Never. Not once.

[Amanda's Sister Amy Lee / Friends]

I never heard his name.

[Seth Green (Amanda's Boyfriend)]

The detectives told me right when they found it, asking me if I knew the name. Like, no idea.

[Michelle Penna (Amanda's Mother)]

It is such a long shot, but they zone in on that, and they decide they need to find out who Dennis is.

[Detective Ronald Gibbons]

One of the things that was missing was her cell phone. We went back to her cell phone Records. We came out that there was phone calls for a number that came back to a Dennis Rosa Roman. I immediately recognized the name because about a year before I had actually arrested Dennis Rosa Roman.

[Narrator]

Givens had arrested Rosa Roman on a misdemeanor charge of disorderly conduct. Rosa Roman pled guilty and paid a fine. But now Gibbons knew exactly who Dennis Rosa Roman was. The question, was this the same Dennis whose name was on that whiteboard?

[Detective Ronald Gibbons]

You have anything further you want to tell us?

[Narrator]

A possible answer could lie in one of the police interviews with Amanda's ex boyfriend, Jesse.

[Detective Ronald Gibbons]

While Jesse was still dating Amanda, Amanda had told him that she thinks her apartment had been broken into while she was at work.

[Seth Green (Amanda's Boyfriend)]

She thought it was some kid that she had met about.

[Detective Ronald Gibbons]

Jesse described him as being shorter. Jesse's probably like 5, 10, 6ft.

[Seth Green (Amanda's Boyfriend)]

He's got to live like somewhere within like 2 second walk from there. That memories to see him walking around like that area all the time.

[Narrator]

Jesse said Amanda told him she had hung out with the person once before, but he had no idea where. Now Detective Gibbons is wondering if the man Jesse had been describing in that interview could have been Dennis Rosa Roman. Amanda lives about a half a block away from this park. She used to hang out here, right?

[Detective Ronald Gibbons]

Yeah. This is like a hangout for the neighborhood. And we learned later on this is kind of like where Dennis would hang out during the daytime because it just didn't work.

[Narrator]

So they might have come across each other in this park just in passing in the neighborhood.

[Detective Ronald Gibbons]

Exactly. Exactly.

[Narrator]

In the time since Amanda's murder, Dennis Rosa Roman had moved from Chicopee to nearby Westfield, Massachusetts. Gibbons decides to pay him a visit. So now we're headed to Westfield, Massachusetts. Why is that significant?

[Detective Ronald Gibbons]

That's very significant. Because once we found the dentist was here on the whiteboard and his number is on the phone, we want to locate Dennis.

[Narrator]

What's your expectation going there? What are you trying to achieve?

[Detective Ronald Gibbons]

The plan was to knock on his door and talk to him, just like we had Talked to over 50 other people in the case, as well as to get his shoe size, as well as to get his DNA. I go to the apartment, ring the doorbell, no answer. And next thing you know, I see from a side alleyway that's between the building, Dennis come out.

[Narrator]

And what happens next?

[Detective Ronald Gibbons]

Beautiful timing. But here he is. He comes right around the corner, just walking right to you, Walking right to us. So I stop him and say, hey, Dennis, you got a moment? We want to talk to you about Chicopee. We want to talk about a Girl named Amanda Plass.

[Narrator]

Yeah.

[Detective Ronald Gibbons]

His first thing is he kind of chuckles. He says, oh, no, I don't go to Chicopee. It's too dangerous there. And I say, well, how about this girl, Amanda Plass? And he says, I don't know Amanda at all. So I know that from the phone records. Yes, he does know Amanda Plass.

[Narrator]

In fact, Gibbons knew from those phone records that there were nine calls between Dennis and Amanda. Dennis had called Amanda five times just a month before the murder.

[Detective Ronald Gibbons]

I said, hey, can we go to the police station? He said, no, no, I got something I gotta do. I notice him light up a cigarette, and he's smoking on a cigarette. And now I'm thinking, wow, maybe I can get DNA off this cigarette that he's smoking.

[Narrator]

Although Gibbons had arrested Rosa Roman a year prior, because he had never been convicted of a felony, his DNA was never entered into the national database. Gibbons says Rosa Roman didn't want to talk to him that day and began to walk away, but not before he tossed the cigarette he was smoking on the sidewalk.

[Detective Ronald Gibbons]

Meanwhile, I told my partners, go to my car, get a paper bag, give me some rubber gloves. Dennis sees that because he keeps looking back. My partner's come back with rubber gloves. He sees me put them on, he sees that paper bag. He sees me reach down and put that inside that bag.

[Narrator]

Two days later, Dennis Rosa Roman is sitting in an interview room at the Westfield Police Department.

[Dennis Rosa Roman (Accused)]

So your first name is Dennis, right?

[Seth Green (Amanda's Boyfriend)]

Yes.

[Dennis Rosa Roman (Accused)]

D N N I s engaging in.

[Narrator]

A high stakes game of cat and mouse with investigators.

[Dennis Rosa Roman (Accused)]

I don't feel right doing this at all, but I have. You don't even understand. I'm trying to save my life here.

[Narrator]

Outside his home, Dennis Rosa Roman appears to be acting cool and calm with detectives until he sees them pick up his cigarette butt off the street. Clearly he's concerned because not long after they leave, he calls Lieutenant Ronald Gibbons.

[Detective Ronald Gibbons]

After seeing me take that cigarette butt, he's now blowing my phone up. Hey, you and I gotta talk.

[Dennis Rosa Roman (Accused)]

You say you really need to talk today. Yeah, like, seriously, where do you guys want me to start?

[Narrator]

Where they want him to start when they meet with the cameras rolling is very simple. Does he know Amanda Plass?

[Dennis Rosa Roman (Accused)]

You knew her? I met her. I didn't know her that long, but I know her other. You know her first name, Amanda. How much before did you meet her and that she passed, right? Say like a week or two. Two weeks the most. So you know her about a week or two before she got killed?

[Detective Ronald Gibbons]

Yeah. He didn't know Amanda at all. And then he comes around to say that, okay, I did know Amanda, but I would sell her weed.

[Dennis Rosa Roman (Accused)]

I met her by Emmy daughter and Tadeshi and chickadee. Okay, you know where that's at? So I seen her, you know, she asked me if I could get some buns. How many times previously did you. It's only been like, three times. The most you ever been to our apartment. Like, up the stairs. And that's about it. I've never stepped in her house. I've never seen the inside of her house.

[Narrator]

As Dennis is talking, he notices detectives checking out his sneakers.

[Dennis Rosa Roman (Accused)]

Like my shoes? Yeah, Nikes, Air Mackeys.

[Detective Ronald Gibbons]

What he wears into the station that particular day is this black Air Max shoe. And we took the aha moment to say, you know what? Can you take off your shoe? And I'm going to take a picture of your shoe.

[Dennis Rosa Roman (Accused)]

My feet stink. I'm sorry.

[Detective Ronald Gibbons]

Because the crime scene itself had imprint in blood.

[Narrator]

The print that you found on the scene, what size was that?

[Detective Ronald Gibbons]

That was a size seven and a half Nike shoe.

[Narrator]

And what size is the shoe that we're looking at?

[Detective Ronald Gibbons]

This is a size 6.7.5 Nike shoe.

[Narrator]

Remember, detectives have had no luck matching those bloody shoe prints to previous suspects. So according to Gibbons, this is potentially damning if confirmed, but still not as conclusive as a DNA match to what was found under Amanda's fingernails. So Gibbons says they get Rosa Roman to agree to a DNA mouth swab.

[Dennis Rosa Roman (Accused)]

Just open your mouth. This is gonna rub that in the center of your lips.

[Narrator]

Givens says he wants Rosa Roman directly tested in case that cigarette butt sample might somehow be contaminated.

[Dennis Rosa Roman (Accused)]

Doing great. Under your tongue.

[Narrator]

There's a really big difference between you thinking, hey, I think we got our guy, and you lining it up with the evidence.

[Detective Ronald Gibbons]

This is a matter of facts.

[Dennis Rosa Roman (Accused)]

So the day that this all happened, what happened that day?

[Narrator]

So Rosa Roman starts telling detectives his version of what happened the day Amanda was killed.

[Dennis Rosa Roman (Accused)]

I brought her some lien. Did she call you like that day? Yeah, she called me that day. She said, yo, can you leave me a dime bag? She was not the one that came to the door. Like, the guy opened the door, he just said, yo, give me that. And that's it. And I went about my way.

[Detective Ronald Gibbons]

What Dennis says is that this other guy was at the apartment.

[Dennis Rosa Roman (Accused)]

I didn't bother saying anything to the guy. The guy looked suspect, like, he looked suspicious.

[Narrator]

He answers detectives questions about what he says the man looked like.

[Dennis Rosa Roman (Accused)]

I'm six feet. So what are you saying? Five, ten, maybe? He's taller than you. Taller than me? Yeah. He has, like, dirty blondish hair. Would you say white? Yeah, he's white. Say he weighs, like, about 171. 190 the most. Almost 200 pounds.

[Narrator]

And goes on to describe what he claims he heard while outside the apartment.

[Dennis Rosa Roman (Accused)]

I'm listening to this guy's like, I want my money. I didn't give you this for no reason. Why would you do this to me? That was the guy's voice?

[Michelle Penna (Amanda's Mother)]

Yeah.

[Narrator]

You're asking him questions about the description of the man who made these comments from inside the apartment. Why are you asking about that?

[Detective Ronald Gibbons]

Because I want to lock him into a story. Will you be consistent with that story, or you go on another tangent?

[Dennis Rosa Roman (Accused)]

So the guy said something to her like, I want my money. I didn't do this. I want my money. I didn't do this for nothing. For nothing. Great. Did you hear her voice? No, I didn't. I didn't hear nothing.

[Narrator]

Rosa Roman is consistent, even though Gibbons says he is convinced Rosa Roman is making up his story.

[Dennis Rosa Roman (Accused)]

That's all about everything. I know, and I can't say no more, no less. You know what I'm saying? Julia? I'm sorry, guys. I'm actually helping you guys, you know what I'm saying? You're very helpful, because you know what? Not too many people have told us that he saw the guy there, you know, so that. You're aces with me.

[Detective Ronald Gibbons]

You know, I didn't have enough to arrest him at this point. I had to allow him to leave.

[Dennis Rosa Roman (Accused)]

Thank you very much.

[Narrator]

One interview ends, but Rosa Roman isn't done answering questions.

[Dennis Rosa Roman (Accused)]

Two days later, this picture is inside her apartment. You ever seen this room?

[Narrator]

It's a photo of that whiteboard. What will Rosa Roman have to say when he's shown? His name is on it.

[Dennis Rosa Roman (Accused)]

And see, right here, it says Dennis was here. Dennis, thank you very much for coming in. Fine, dude. And you've been very cooperative with us, and we appreciate it.

[Narrator]

Dennis. Rosa Roman agrees to another interview.

[Dennis Rosa Roman (Accused)]

I wish I knew more to help you guys.

[Narrator]

Repeating the story. Detectives say they don't believe that he never entered Amanda Plass's apartment the day of her murder. After he claims some man answered her door.

[Dennis Rosa Roman (Accused)]

I'm gonna give her some leave. He's like, well, she's busy right now. And I give it to him. He shuts the door. Dumb, hard, in my face, and that's it. Okay, this guy's mad, and I'm about to leave, like, and I left.

[Narrator]

You know what?

[Dennis Rosa Roman (Accused)]

I'm saying.

[Narrator]

But Rosa Roman says that was long enough for the man to recognize him.

[Dennis Rosa Roman (Accused)]

I feel like this guy's gonna run into me one day and just like, try to face on me or hurt me or something. And that's when I'm gonna peel my ass to the police station. Yeah. Is that because he saw you that day? Like this guy knows what I look like.

[Narrator]

But what Rosa Roman doesn't know is that Gibbons is expecting critical evidence to the case to come back at any moment. The results from his DNA swab.

[Dennis Rosa Roman (Accused)]

You were asking me about this picture.

[Seth Green (Amanda's Boyfriend)]

Yeah.

[Detective Ronald Gibbons]

Yeah.

[Dennis Rosa Roman (Accused)]

I want to see it.

[Narrator]

So before that happens, Gibbons confronts Rosa Roman for the first time about that all important whiteboard where it says Dennis was here.

[Dennis Rosa Roman (Accused)]

This picture is inside her apartment. You ever seen this room? First time I'm seeing it.

[Detective Ronald Gibbons]

We said first time I'm seeing it. And then. Well, how about this? This whiteboard that's in the back room.

[Dennis Rosa Roman (Accused)]

And see right here, it says Dennis was here. Oh, yeah, I do remember that. I wrote my name on that. You wrote your name on that? Yeah, yeah, yeah, yeah, I wrote my name on that.

[Narrator]

So he's admitting to you that that's his name on the whiteboard.

[Detective Ronald Gibbons]

You've told me all this time you've never been in an apartment, and now I got you in there.

[Dennis Rosa Roman (Accused)]

So you signed Dennis was here, right? You didn't put the date? No, I didn't.

[Narrator]

Okay.

[Dennis Rosa Roman (Accused)]

I don't even know why that's there. I don't. Yeah, but you remember this dry erase board? Yeah, I do. Where was the dry erase board? In the back of, you know, the door when you come in? Yeah, I was right there.

[Michelle Penna (Amanda's Mother)]

As he is confronted with the evidence, he shape shifts. He manages to keep changing his story to try to ameliorate the facts in front of him. There are certain kind of people who can make up things on the fly and change their narrative based on the clues that are being given to them.

[Dennis Rosa Roman (Accused)]

You say you've never been inside her place? Well, I have been in her house, but I just don't. I don't want people to, like, look at me like if I'm a murderer.

[Detective Ronald Gibbons]

So now this is the first time that he actually puts himself in the apartment.

[Dennis Rosa Roman (Accused)]

But you went in the apartment. How many other times had you been inside that apartment? Twice. Two times. That's it. And what were they for? To bring her weed and smoke the bone and sign this. So the room that you were in were that back room, the kitchen and the back room. That's about it.

[Detective Ronald Gibbons]

The back Room was where the whiteboard was.

[Narrator]

So what are you putting together at this point?

[Detective Ronald Gibbons]

I'm putting together at this point that he, in fact, had not only been in that back room, he'd also been in the kitchen at some point where the crime occurred.

[Narrator]

Remember, Amanda had told friends she suspected someone had broken into her apartment. And Dennis says she had asked him about that.

[Dennis Rosa Roman (Accused)]

You said that Amanda approached you about somebody breaking into her place? Yeah, she asked me like, yo, somebody came into my house. Do you guys know? And I was like, well, I really don't know. Like, I don't know what to tell you Now.

[Narrator]

Gibbons suspects that someone was Rosa Roman. Then, a few minutes later, a huge development. The detectives get called to leave the interrogation room.

[Dennis Rosa Roman (Accused)]

Give me one second. How much longer is this going to take? 5 minutes.

[Narrator]

Outside, they get the news. The DNA results are in. Rosa Roman is a match for what was found under Amanda's fingernails. They soon dropped that bombshell on him directly.

[Dennis Rosa Roman (Accused)]

The DNA that was found under her fingernails connects you to her. You know what? It doesn't just get there.

[Detective Ronald Gibbons]

Dennis is now thinking in his mind, how do I get out of this?

[Narrator]

And what he tells them next totally flips the story on its head. He now claims he tried to save Amanda.

[Dennis Rosa Roman (Accused)]

I know the murderer and I tried to save her life.

[Narrator]

What's he trying to do here?

[Detective Ronald Gibbons]

He's trying to create a situation of why we have his DNA, why his DNA is possibly on her.

[Narrator]

He's casting himself almost as the hero in this.

[Detective Ronald Gibbons]

Yes, he is.

[Dennis Rosa Roman (Accused)]

Well, why don't you tell us everything that happened in the environment. I know the murderer. That's all I know. I can't give you no more. I'm sorry that you said he tried. I want a lawyer. I want a lawyer. Okay.

[Narrator]

Gibbons says, asking for a lawyer, stops the interrogation room recording immediately. So you don't see the scuffle that he says breaks out when detectives handcuff Rosa Roman and place him under arrest.

[Dennis Rosa Roman (Accused)]

You don't have to be aggressive with me, dudes. You didn't have to be that aggressive.

[Narrator]

And then they have him booked. He's charged with first degree murder. This is over two years after Amanda was killed. They tell you we are making an arrest.

[Michelle Penna (Amanda's Mother)]

Yep.

[Narrator]

What did you think?

[Michelle Penna (Amanda's Mother)]

Finally, finally. You know, you always wonder why, why, why?

[Narrator]

Dennis, though, is admitting nothing.

[Dennis Rosa Roman (Accused)]

What are you guys trying to do, pen me for this murder, too? My DNA may be on her body, my DNA may be at the house, but you guys really don't know what went down.

[Narrator]

But after he's transported from the Westfield police department to Chicopee, he's about to explain.

[Detective Ronald Gibbons]

He demanded to speak to myself and Watson again. So you, he didn't come to the door, you actually went inside?

[Dennis Rosa Roman (Accused)]

I went inside. I barged in.

[Detective Ronald Gibbons]

Was the door open?

[Dennis Rosa Roman (Accused)]

The door was unlocked.

[Narrator]

As Rosa Roman tells them the newest version of his story, he now claims when he hears the commotion inside Amanda's apartment, he rushes in and fights the man he says was trying to kill her.

[Detective Ronald Gibbons]

What do you see when you get to the kitchen?

[Dennis Rosa Roman (Accused)]

I see the guy on top of her.

[Detective Ronald Gibbons]

When you say he was on top of her, where was she at?

[Dennis Rosa Roman (Accused)]

She was on the floor.

[Detective Ronald Gibbons]

What are you doing?

[Dennis Rosa Roman (Accused)]

I'm tussling with the guy, trying to get the knife out of his hand, and he's just like thrusting it, thrusting it and thrusting it forward towards me. And I'm like trying to back up and. And I try to like grab Amanda and she scratched me. She scratched me. Yeah, she got some skin off of me, but that was because I was trying to save her.

[Narrator]

That's right. Rosa Roman now claims he tried to save Amanda. This is the key to his new story. His explanation for why his DNA is under Amanda's fingernails, even though he says he didn't kill her.

[Dennis Rosa Roman (Accused)]

And after that, me and him were tussling and the guy punches me in the jaw and I run out the door.

[Detective Ronald Gibbons]

And that's what his story was, that this guy is now following him around town. He's now being threatened by this guy because this guy doesn't want the truth to come out. What did he tell you?

[Dennis Rosa Roman (Accused)]

Yo, you snitch on me, I'm gonna kill you just like that. Like I know I killed her. And that's it, it's done.

[Narrator]

But now Rosa Roman has to tell that story in court. The trial. The man accused of killing 20 year old Amanda Plass is getting underway today in Springfield. And he says he can identify who Amanda's killer is.

[Michelle Penna (Amanda's Mother)]

Amanda Plass's parents sat hand in hand with justice for Amanda bracelets on as they waited for the murder trial of their 20 year old daughter to begin. I think I broke down more so in the courtroom just looking at him.

[Amanda's Sister Amy Lee / Friends]

It's kind of hard to describe how it felt to see him for the first time. It's like a fever dream. Like, is this really happening? But my mind was not on him. My mind is on my sister. When I was selected for the jury, it was surreal. It was definitely a bit of a, oh my God, what am I in for? The home that Amanda lived in was Two houses from where my mother grew up and my grandmother lived. It just became very personal. Evidence in this case will show that on Friday, August 26, 2011, Amanda Platz was brutally murdered in her home. Ms. Class was getting ready to go to work when the defendant came into her apartment while she was getting ready and stabbed her six times.

[Narrator]

Prosecutors lay out their case against Dennis Rosa Roman. There are the bloody footprints in his shoe size, his palm print on the broken window, and his DNA under Amanda's fingernails. They argue that Dennis and only Dennis committed this crime.

[Amanda's Sister Amy Lee / Friends]

One set of bloody footprints, One major male DNA profile underneath both her right hand and left hand fingernails. One killer, one defendant. They literally took us from A to B to C to D. They laid out every single piece of evidence. They correlated every piece of evidence to him.

[Narrator]

In addition to the physical evidence, prosecutors also used Dennis own words against him.

[Dennis Rosa Roman (Accused)]

And see, right here it says Dennis was here. Oh, yeah, I do remember that. I wrote my name on that.

[Amanda's Sister Amy Lee / Friends]

Each time he's confronted with evidence, he changes his story to fit the evidence.

[Detective Ronald Gibbons]

I think it was important for them to see the three interviews because it showed Dennis as agreeing to some of the facts, denying some of the facts, and then coming around and changing the stories repeatedly.

[Narrator]

But while the prosecution says the evidence proves Dennis guilt, the defense argues that it isn't what it seems. He was in her apartment when Linda Class was killed.

[Detective Ronald Gibbons]

He did not do it, but he.

[Narrator]

Knows the guy who did.

[Michelle Penna (Amanda's Mother)]

The last story he told was that he was there with another man and he saw the other man kill Amanda. But he will never give the name because he was afraid the killer would kill his family.

[Narrator]

And he tells you how many times.

[Detective Ronald Gibbons]

He'S afraid for himself.

[Narrator]

He's afraid for his family.

[Dennis Rosa Roman (Accused)]

Charge me.

[Narrator]

I'm not giving up his name. My name pops up. Meaning if they capture him, if my name pops up, he's gonna kill me. Dennis version of events kept changing over those three police interviews. In his final one, Dennis had a new detail for detectives that the alleged killer was none other than his own drug dealer.

[Detective Ronald Gibbons]

Your dealer went to her house?

[Narrator]

Yeah.

[Dennis Rosa Roman (Accused)]

Your dealer, my dealer.

[Detective Ronald Gibbons]

The two of you walk in the aisles together.

[Michelle Penna (Amanda's Mother)]

He had said he was there because he had given Amanda pot and she had not paid. So he said that the drug dealer killed Amanda, and he saw it yelling.

[Dennis Rosa Roman (Accused)]

Like, yo, why are you. I'm gonna get you your money. And I try to grab her, and she, like, grabs my arm. And he just keep going and going and going and going.

[Detective Ronald Gibbons]

What do you mean he's going and.

[Dennis Rosa Roman (Accused)]

Going he's stabbing her, he continuously stabbing her. And she just collapsed on the floor after I separated her.

[Detective Ronald Gibbons]

Think she was dead.

[Dennis Rosa Roman (Accused)]

I know she was dead. I was just thinking to myself, like, how do I get myself out of this?

[Detective Ronald Gibbons]

Defense strategy was basically that the police should look further.

[Amanda's Sister Amy Lee / Friends]

They continually brought up other people to say, well, it could have been them or it was them or it was this or just to try to have a sense of doubt.

[Narrator]

After eight days of testimony, the fate of Dennis Rosa Roman now rests with the jury.

[Amanda's Sister Amy Lee / Friends]

When we retired to the jury room to deliberate, we. We took a photo of Amanda. It was a close up of her face with her smile, and we hung that in the jury room just so we could remember why we were there and what this was all about. It was hard. You don't ever want to think of your best friend going through something that awful. And that was her final moments. And then bringing that into the trial, it was just.

[Detective Ronald Gibbons]

It's terrible.

[Amanda's Sister Amy Lee / Friends]

To this day, it's just. There's no words.

[Narrator]

After only five hours of deliberation, the jury reaches a verdict.

[Michelle Penna (Amanda's Mother)]

We were sitting in the DA's office in the break room, and next thing you know, you hear running down the hall that the jury came back.

[Amanda's Sister Amy Lee / Friends]

Breaking news this hour.

[Michelle Penna (Amanda's Mother)]

A guilty verdict today in the Amanda Plass murder trial.

[Detective Ronald Gibbons]

The jury today found Dennis Rosa Roman.

[Narrator]

Guilty of first degree murder.

[Amanda's Sister Amy Lee / Friends]

We had a couple jurors who weren't quite sure. One of them wanted to review a bunch of evidence again. And his commentary the whole time was, look at him, he's lying. He keeps changing his answers. And we very quickly came to a unanimous decision that Dennis was guilty.

[Michelle Penna (Amanda's Mother)]

In that moment, you felt relief, definite relief. Now I can put an end to this chapter.

[Narrator]

Despite a guilty verdict, there's still the unanswered question hanging over this case. And that's, why did Dennis Rosa Roman kill Amanda Plass in the first place? Dennis Rosa Roman has been found guilty of the murder of Amanda Plass. But the one mystery that still remains.

[Michelle Penna (Amanda's Mother)]

I don't know why. There's only one person who knows why. And he never spoke. So that's definitely the hardest of it. There wasn't a bad bone in that child's body. She never did anything wrong to anybody.

[Narrator]

Lt. Gibbons has developed his own theory as to why he believes Dennis Rosa Roman murdered Amanda. He says he learned during the investigation that there was a bag of marijuana inside Amanda's apartment left behind by someone else. Gibbons says investigators were never able to find that bag and suspects Dennis broke in looking to steal it.

[Detective Ronald Gibbons]

Dennis is a low level dealer in the neighborhood. My theory is that he wanted to steal that weed that was in the apartment and a man to just be was a victim of circumstances that she happened to be there when he arrived.

[Narrator]

Before Rosa Roman is sentenced, Amanda's mother, surrounded by family, tearfully addresses the court.

[Michelle Penna (Amanda's Mother)]

On August 26, 2011. My world was forever changed. My pain does not end here, but my healing begins. I think at that point it was finally my time to tell him, you took something precious from this world and I hope you never see the light of day again. There is no amount of time that will ever bring Amanda back. I would like to ask court to hand out the highest sentence possible of life without fuel.

[Narrator]

It's the justice Michelle Penna has spent more than five years fighting for. Court has hereby sentence you to the Massachusetts Correctional Institution at Cedar Junction for the term of your natural life without the possibility of parole. As you look at him and you see that he's getting life without parole, what emotions are going through you?

[Michelle Penna (Amanda's Mother)]

At that time, it was a relief knowing that we were finally at another closing point.

[Narrator]

Did you feel like justice had been served?

[Michelle Penna (Amanda's Mother)]

That justice will never be served because she's dead and he's not.

[Narrator]

As for those officers who snapped those photos of Amanda's body, at her most vulnerable moment, the mayor of Chicopee released a written apology. Michelle also reached a resolution in the lawsuit she filed.

[Detective Ronald Gibbons]

Plass's family sued the city of Chicopee and the police department.

[Narrator]

The lawsuit was settled for $110,000. Michelle continued her fight and helped pass Amanda's law.

[Michelle Penna (Amanda's Mother)]

The bill bans first responders from taking and sharing unauthorized pictures of crime victims.

[Amanda's Sister Amy Lee / Friends]

For an officer to want in that moment to take a picture of a scene like that, it makes my stomach turn. My mom wanted to make it known that you're never doing that again.

[Narrator]

Today, Michelle keeps Amanda's memory alive by sharing her story with college students.

[Michelle Penna (Amanda's Mother)]

This is about the path that I have taken, the path that has helped me to my healing process. I want people to know that grief never goes away. But dealing with it or trying to deal with it or put a band aid on it enough to get you through every day is what you have to do.

[Narrator]

Thank you again.

[Michelle Penna (Amanda's Mother)]

Thank you so much.

[Amanda's Sister Amy Lee / Friends]

Oh, these are great. That's her and Brandon. Brandon is my son. See just how the happiness on his face and her big smile. I have always said that Amanda passing kind of saved my life because I knew that I wanted to make her proud. She really helped me become the woman who I am today.

[Seth Green (Amanda's Boyfriend)]

She was just a very kind person and, and wanting to help the world be better. And that's just something I hope everyone can try to do, you know?

[Narrator]

Do you feel like she's with you now?

[Michelle Penna (Amanda's Mother)]

Oh, absolutely. All the time.

[Narrator]

If you could have one more minute with her, one more second to say something to her, what would you say?

[Michelle Penna (Amanda's Mother)]

What she always said and what she always did. Keep your face to the sun. Never look back at your shadows. Just like her precious sunflowers.

[Narrator]

DENNIS Rosa Roman appealed his conviction, but it was denied. And David even though he was sentenced to life without parole, there's still a chance he could walk free one day as early as 2028.

[Detective Ronald Gibbons]

A Massachusetts court has ruled that it's.

[Narrator]

Unconstitutional to sentence offenders under the age.

[Detective Ronald Gibbons]

Of 21 to life without parole. Rosa Roman was 20 at the time of Amanda's murder. Her family tells 2020 they plan to fight this new ruling. That's our program for tonight. I'm David Muir.

[Narrator]

And I'm Debra Roberts. From all of us here at ABC News and 20 20, Everyone deserves to be connected. That's why T Mobile and US Cellular are joining forces.

[Detective Ronald Gibbons]

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[Narrator]

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[Dennis Rosa Roman (Accused)]

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[Narrator]

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[Detective Ronald Gibbons]

Savings with three plus lines include third line free via monthly bill credits.

[Narrator]

Credits stop if you cancel any lines.

[Seth Green (Amanda's Boyfriend)]

Qualifying credit required.