REOPENED: Office Politics

Summary

---

Cold Case Files: REOPENED: Office Politics

Date: October 23, 2025
Host: Paula Barros
Podcast: Cold Case Files (A&E / PodcastOne)

---

Episode Overview

This episode revisits the chilling 1989 murder of Sharon Bloom, a dedicated employee at Minnesota’s 3M Worldwide, who tragically became the target of escalating workplace harassment. After her sudden disappearance and the subsequent discovery of her body, investigators struggled with scarce evidence and dead ends—until advances in forensic technology years later finally broke the case open. The episode chronicles the persistent efforts of law enforcement, the profound impact on Sharon’s loved ones, and a long-awaited resolution decades after the crime.

---

Key Discussion Points & Insights

1. The Harassment and Disappearance of Sharon Bloom

• Escalating Hostility: Sharon Bloom, 38, endowed with a recently-earned promotion, became the victim of workplace pranks that evolved into targeted harassment—missing personal items, sabotaged documents, and more.
  • “One day she came home and was in tears and her reaction was what could I have done to somebody that could cause them to hate me so much?” — David Cofode, Sharon’s boyfriend [00:57]
• The Day Sharon Vanished: On November 2, 1989, after a typical morning in the office, she was seen leaving for lunch but then disappeared. Her car remained in the company parking lot, and repeated calls to her desk went unanswered.

2. Early Investigation and Suspicions

• Immediate Concerns: Despite Sharon missing only a short while, her boyfriend’s proactive efforts led to the upsetting discovery that her car was still at work.
• Red Flags: Lead Investigator Hines immediately sensed foul play, given Sharon’s abandoned car and missing status.
  • “That was the first strong indication from my perspective anyway, that there was something else involved here.” — Investigator Hines [02:55]
• Workplace Rivalry: Attention soon gravitated to Stephen Zanter, a coworker and failed contender for Sharon’s promotion, who provided a questionable alibi no one could confirm.
  • "He offered us an alibi right away, but it was an alibi that wasn't alibi ing him. It was an alibi that made no sense." — Investigator Hines [04:02]
  • “We have a guy who's a problem. We have a guy who others think could be capable of harassment. He's given us an alibi that is just really, well, lame.” — Investigator Hines [05:02]

3. The Discovery of Sharon’s Body

• Grim News: One week after her disappearance, Sharon’s body was found in a cornfield 50 miles from the city.
  • “She obviously had trauma, and beyond that, there was no sign of any struggle. It had looked as if she had just been placed there.” — Sgt. Barry Cummins [09:28]
  • Evidence suggested sexual assault, and hairs at the dump site that did not belong to Sharon were collected.

4. Zanter’s Disturbing Reaction

• Confrontation and Collapse: When told of Sharon’s death, Stephen Zanter broke down dramatically, behaving catatonically—fueling investigators’ suspicions.
  • “[He] became almost convulsive, and he was on the floor…pulled his legs up to him in the fetal position and rocked back and forth…just moaned.” — Investigator Hines [10:39]
• Forensic Letdown: Autopsy findings did not yield physical evidence tying Zanter to the murder—no semen, just premenstrual discharge—leaving investigators at an impasse.

5. Cold Case Reopened & A New Approach

• Agent DePrima’s Theory: Reopening the case, Agent Ray DePrima suspected Zanter’s rage over losing the promotion as the motive.
  • “He was so enraged that he didn't get that promotion and that this what a woman that he perceived as below him, that she got it, that caused him to act.” — Agent Ray DePrima [11:46]
• Pivotal Lead: Focus shifted to Zanter's wife, Barbara, who had made unsettling remarks about cleaning blood from new carpeting—coincidentally the day after Sharon vanished.
  • “She brought up the fact that she wanted to know if anyone knew how to get blood out of their new carpeting...Steve had had an accident or something and he got blood all over…” — Joe Sorenson [12:27]
  • The blood was described as “splattered” and traced up the stairs, raising suspicions.

6. Covert Operation & Confession

• Secret Recording: Barbara’s colleagues agreed to secretly record a conversation, revealing that she hid the incident from police to avoid further trouble for her husband.
  • “Why didn’t you tell the police about the blood? Because I...just didn't. I didn't want to give him any more to do.” — Barbara Zanter [16:14]
• Probable Cause Established: The conversation facilitated a search warrant for the Zanter residence.

7. Forensic Breakthrough and Setbacks

• Evidence Find: During the search, luminol revealed blood on the carpet, and Sharon’s keys were discovered in the basement.
  • “We get this great fluorescence and we knew that we had blood.” — Agent Ray DePrima [18:07]
  • "A set of keys that were later identified as keys belonging to Sharon Bloom." — Sgt. Barry Cummins [18:33]
• Legal Hurdle: The keys were suppressed as evidence by the Minnesota Supreme Court, citing search and seizure overreach.
  • “They threw the keys out, claiming we had overstepped our bounds, that we didn't have probable cause to seize the keys…” — Agent Ray DePrima [19:13]

8. Final Resolution with DNA

• DNA Advances: By 1999, forensic science could extract viable DNA from the carpet stains—despite attempted cleaning—linking it definitively to Sharon Bloom.
  • “The blood then on the carpeting matched the DNA profile from the blood of the victim.” — Ann Marie Gross [21:12]
  • Hair found at the dump site also matched Zanter.
• Confession and Sentencing: Confronted with incontrovertible DNA evidence, Zanter confessed in 2003 and received a 25-year prison sentence.

---

Notable Quotes & Memorable Moments

• Sharon’s Vulnerability:
  • “One day she came home and was in tears and her reaction was what could I have done to somebody that could cause them to hate me so much?” — David Cofode [00:57]
• Zanter’s Alibi Called Out:
  • “He offered us an alibi right away, but it was an alibi that wasn't alibi ing him. It was an alibi that made no sense.” — Investigator Hines [04:02]
• Barbara’s Rationalization:
  • “She was trying to convince herself…He didn't do this, and they're out to get us.” — Joe Sorenson [15:50]
• On Justice and Closure:
  • “If this was the justice then I will have to accept doesn't mean that I sometimes feel it still falls short.” — David Cofode [21:50]

---

Key Timestamps

• 00:57 — David Cofode recounts Sharon’s distress over harassment
• 02:55 — Investigator Hines expresses early suspicion of foul play
• 04:02 — Initial doubts about Stephen Zanter’s alibi
• 09:05 — Discovery of Sharon’s body in a cornfield
• 10:14 — Zanter’s breakdown upon hearing of Sharon's death
• 11:46 — Agent DePrima shares his theory about motive
• 12:27 — Barbara Zanter’s blood-cleaning story emerges
• 16:14 — Barbara admits to withholding blood evidence from police
• 18:07 — Blood evidence found with luminol at the Zanter home
• 19:13 — Keys suppressed as evidence by state Supreme Court
• 21:12 — DNA finally links blood from carpet to Sharon Bloom
• 21:50 — David Cofode reflects on justice being served, but falling short

---

Tone & Narrative Flow

The episode maintains a measured, investigative tone, interspersed with the emotional testimonies of Sharon’s loved ones and the frustration of law enforcement at every new dead end. Triumph and sorrow are palpable, culminating in a bittersweet resolution as true justice is delayed for years, but ultimately achieved through the relentless evolution of science and perseverance.

---

Transcript

[Agent Ray DePrima]

An A and E original podcast, this.

[Narrator]

Episode contains descriptions of violence and sexual assault. Use your best judgment. In 1989, 3M Worldwide was the largest employer in the state of Minnesota. One employee, 38 year old Sharon Bloom, was working hard to make her way up the corporate ladder. After a promotion, it became clear that it wasn't only Sharon's superiors that had noticed her work. And she became the victim of office pranks that escalated into harassment. Personal items like her keys or glasses would go missing, only to show up a few days later. Some presentations and documents that Sharon was working on were taken from her desk and a pot of coffee was even dumped onto her chair. This is Sharon's boyfriend, David Cofode.

[David Cofode]

One day she came home and was in tears and her reaction was what could I have done to somebody that could cause them to hate me so much?

[Narrator]

On November 2, after her commute from her suburban home in Woodbury, she arrived at the office around 7.30am she worked until around noon and then was seen with her coat on, likely going to get lunch that afternoon. None of the calls to her cubicle were answered and Sharon didn't make it home for dinner. Her body was found a week later. Sharon had been murdered. From A and E, this is Cold Case Files. When Sharon didn't get home at the usual time, her boyfriend David started to worry.

[David Cofode]

So at about 7, I started to call her friends. There was only two places I thought that she might have gone to.

[Narrator]

And.

[David Cofode]

She wasn't an either.

[Narrator]

Sharon hadn't been missing long enough for the police to start an investigation. So David called Sharon's company and asked the night shift workers if they could take a look in the employees parking lot.

[David Cofode]

And at 11 approximately I got a call back. They told me her car was still in the parking lot. I found that you can get really no information from anybody. You can't call the highway patrol, you can't call hospitals, you can't call anyone.

[Narrator]

He waited up all night by the phone hoping to get a call from Sharon. But the phone didn't ring. In the morning, David filed a missing persons report with the Woodbury Police Department and reported that her car was still in the company's parking lot. The case was signed to investigator David.

[Investigator Hines]

Hines for her to leave that behind. That was the first strong indication from my perspective anyway, that there was something else involved here.

[Narrator]

Investigator Hines checked with the ticket agents at bus and train stations and also at the airport. He also spoke with car rental agencies, but none of them had any record of Sharon Blum.

[Investigator Hines]

We were quickly Getting to the idea that she had definitely disappeared from the workplace. It didn't take us very long to kind of zero in on the fact that we don't think she was ever back at work.

[Narrator]

After the lunch hour, Hines talked with Sharon's co workers and learned about all the harassing pranks that Sharon had been a victim of.

[Investigator Hines]

There was quite a series of incidents and it was quite clear that this was not just the usual workplace prank kind of thing. This was somebody who was definitely zeroing in on her and harassing her with a purpose.

[Narrator]

Hines discovered that all of Sharon's co workers had come back from lunch and worked through the afternoon except for one man named Stephen Zanter.

[Investigator Hines]

He offered us an alibi right away, but it was an alibi that wasn't alibi ing him. It was an alibi that made no sense.

[Narrator]

In fact, Zanter told the investigator that he had left the office around 11am and ate lunch at a fast food restaurant. After that, Sander said he had car trouble and went home for the rest of the day. Hines felt like his story was a little too convenient.

[Investigator Hines]

He didn't see anybody that he knew. There was nobody that he knew of that could verify any of was really accounted for his time. But it was in a way that he almost went out of his way to let us know that no one.

[Narrator]

Could verify this because of his questionable story. Hines looked further into the working relationship between Sharon and Zanter. Hines discovered the two of them had been up for the same promotion and Sharon had been the one who got it.

[Investigator Hines]

We have a guy who's a problem. We have a guy who others think could be capable of harassment. He's given us an alibi that is just really, well, lame.

[Narrator]

Eight days into the investigation, Hines called the Minnesota Bureau of Criminal Apprehension, the state's premier investigation agency, for reinforcements on the case. Agent Ray Di Prima reviewed the case file provided by Hines and agreed that Zanter's behavior was suspicious. This is Agent deprima.

[Agent Ray DePrima]

There were just gaps in his story. And so we wanted to really zero in on that and you nail him down because he had left 3m about the same time as Sharon Bloom and no one had seen him.

[Narrator]

The investigators questioned Sharon's co workers about Zander's office behavior.

[Agent Ray DePrima]

Steve was always the type of guy that felt that he was smarter. He always felt that he could do a job better. But yet we found out that he was totally isolated at 3m and that everyone thought of him as an incompetent.

[Narrator]

Hines and Diprima visited Zanter at his home to give him a chance to better explain his story. Zanter talked a lot, but didn't provide any new information.

[Agent Ray DePrima]

And he states that his car breaks down and that some good Samaritan came along and opened the hood, jumped his car, and that he went home.

[Narrator]

In order to verify Zanter's story, Investigator Hines asked for information about the person who jumped the car, a possible alibi.

[Investigator Hines]

And we said, well, what guy? And he said, I don't even know what he looks like. He was a guy, though. He was a man. He said, I think so. Okay, what kind of car did he have? I don't know. And we told him, you know your alibi. This is a bad alibi. An alibi like that kind of says to us that you're trying to hide something.

[Sponsor Voice]

You know those workouts where you finish and think, did that actually make me stronger? With hydro, there's no guessing. In just 20 minutes you're working 86% of your muscles. And with the new Hydro Arc, you can actually see your progress measured in power, endurance and precision every single time you row. Hydro really is the most efficient workout out there. It works your arms, legs and core all at once in one smooth, low impact motion. And the new Hydrow Arc takes that experience even further. It's their most advanced rower yet, built to make you stronger and more consistent with every session. What I love most is the Arc's hydrometric system. It tracks your power, endurance and precision after every row. You can literally watch your strength build over time, which is so motivating. Plus it gives you personalized class recommendations based on your progress so you don't have to figure out what to do next. It's all planned for you. And honestly, rowing at home on the Arc feels amazing. Getting a good sweat used to mean hours at the gym. Now I do it all from home and I can actually see how much I'm improving. The machine itself is beautifully made and the classes are filmed on the water. With Olympians and world class athletes in stunning places around the world. It feels like an escape every time I work out. Hydro backs it all with a 30 day risk free trial free standard shipping and a one year warranty. So if you've been wanting a more efficient, motivating way to work out at home, the Hydro Arc just makes sense. Skip the gym, not the workout. Stay on track with the new Hydro Arc, Hydro's most advanced rower yet. For a limited time, go to hydrow.com and use code cold case to get $100 off any hydro rower, including ARC. That's H Y-R-O-W.com code cold case.

[Narrator]

Three hours into the interview with Xanter, Agent Deprima received some news about the case.

[Agent Ray DePrima]

And as we're conducting the interview, my pager went off and I was informed by my supervisor that Sharon Bloom's body had been found in a cornfield.

[Narrator]

50 miles south of the Twin Cities near Northfield. David Sutter had just started harvesting the corn in his field. He hadn't been to that particular area of his farm for over a week. The body was about 20ft from the dirt road north of the field field. Sutter called the Rice County Sheriff's Department immediately. Sergeant Barry Cummins was assigned the case.

[Sergeant Barry Cummins]

She obviously had trauma, and beyond that, there was no sign of any struggle. It had looked as if she had just been placed there.

[Narrator]

Her body was naked from the waist down, which suggested that Sharon had been sexually assaulted.

[Sergeant Barry Cummins]

Seeing someone that way, partially clad, bra pushed up, it had appeared she had been raped.

[Narrator]

Sharon's body was taken to the St. Paul Ramsey Medical center for the autopsy. Biological samples were collected from her body. Human hair had also been found at the dump site that didn't belong to Sharon. Agent DePriema shared the news to the man he suspected might have killed her. Stephen Zanter.

[Agent Ray DePrima]

He fell to pieces. He just sort of dropped. We were in his family room and he became catatonic. He started crying, became almost convulsive, and he was on the floor. He went all the way around his family room on his knees.

[Narrator]

Agent Hines, who was also present, found dancers behavior unusual.

[Investigator Hines]

Then he got up and walked into the living room. His wife kind of was at his side helping him along. And he sat in. They had one of these big wicker rocking chair things that you can kind of put your whole body in. He sat in there, pulled his. Closed his eyes, pulled his legs up to him in the fetal position and rocked back and forth on this thing and just moaned.

[Narrator]

The investigators were unsure of what to make of Zantra's reaction. They hoped that the biological evidence from the autopsy would help provide some answers. But the following day, the coroner informed detectives that the biological samples they thought might be semen were not.

[Agent Ray DePrima]

And he told us what I thought was seminal fluid was not. It was premenstrual discharge.

[Narrator]

Without physical evidence, the investigators weren't sure how to connect Zanter to Sharon's murder. And the case went cold. Two years later, Agent deprima decided to reopen the case.

[Agent Ray DePrima]

My personal theory on this case is that he was so enraged that he didn't get that promotion and that this what a woman that he perceived as below him, that she got it, that caused him to act.

[Narrator]

This time, diprima took a different approach to his investigation. He decided to focus on Zanter's wife Barbara, who worked as an elementary school teacher. This is Joe Sorenson, one of Barbara's co workers.

[Joe Sorenson]

Barbara and I were good friends.

[Narrator]

Joe remembered a meeting at the school where the conversation went from school related topics to. To more personal topics.

[Joe Sorenson]

At that meeting, she brought up the fact that she wanted to know if anyone knew how to get blood out of their new carpeting because they just moved into this new house and Steve had had an accident or something and he got blood all over and she wanted to know if we knew how to remove it.

[Narrator]

According to Barbara, the blood trail went across her new carpet, up the stairs, and into the bathroom on the second floor.

[Joe Sorenson]

She didn't give a lot of detail about the way it looked, except she did use the word splattered.

[Narrator]

Sorensen made a note in her date planner to look up tips on removing blood. The date of that entry was November 3rd, 1989, the day after Sharon Blum had disappeared. Here's Agent Deprima again.

[Agent Ray DePrima]

Well, I'm thinking that we're very, very close because if what they're saying is true, Sharon Blum has been killed in that house.

[Narrator]

In order to verify Joe Sorenson's story, he asked if she and other co workers of Barbara's would be willing to tape conversations with her.

[Joe Sorenson]

He asked if we would be willing to tape conversations with Barb.

[Narrator]

Barbara's co workers didn't like the idea of betraying their friend, but they liked the idea of a murderer roaming free in their neighborhoods even less. Here's Agent deprima again.

[Agent Ray DePrima]

They felt very guilty that they hadn't come forward because this had passed their mind back in 1989, that they should call the police. But they didn't. And they sat on this and so they were feeling sick that they hadn't called the police.

[Joe Sorenson]

What we really felt is we were worried for Barbara because if Steve was capable of doing something like this once, what if he could do it again?

[Narrator]

That was Joe Sorenson who arranged to get together at Barbara's house with a few co workers. Everyone but Barbara knew the conversation was being recorded. Here's some of the audio from the teachers get together.

[Barbara Zanter]

You know, you shared a lot of stuff with us that at the time, all of this chaos, and I don't know. Do they know all of that? What kind of things? Well, tell me what you're thinking of in there. Well, I think the one thing, and I brought it up a little bit when we went for our walk was. And the blood that you found in the house on it was real close to the time when Sharon disappeared. And that bothered me, too. And I questioned Steve about it a couple times and he told me that what happened was he got frustrated trying to work on the car and he just locked it, whacked his hand down, and he cut his wrist. And he didn't, you know, he wasn't thinking clearly. He ran up in the house and he went upstairs because that's where we keep our medical supplies so he could bandage it up. And he said, when I reached for the railing, I think I must have felt faint. And I. I reached for the railing and that's why the blood is at the top of the stairs. We didn't tell the police about all that. They don't know about the blood on the carpet.

[Narrator]

I don't think Jo believed that Barbara was in denial about the situation because she didn't want to believe her husband was capable of murder.

[Joe Sorenson]

I guess I really think that she wanted so much to believe him and to believe in their life that she was trying to convince herself it was that very definitive. He didn't do this, and they're out to get us.

[Narrator]

Here's some more audio from the tape.

[Barbara Zanter]

Why didn't you tell the police about the blood? Because I. I just didn't. I didn't want to give him any more to do.

[Narrator]

They got us with the conversation at the table, provided enough probable cause for a search warrant.

[Sponsor Voice]

Ever had one of those late night online shopping sprees where you're cozy in bed, just scrolling and adding things to your cart, and then you realize your wallet is across the room and getting up feels like a lot of work. That's when you spot it. That purple shop pay button. It's got all your info saved, so with one tap, you're checked out and staying put. That button is a sure sign the store is powered by Shopify. Shopify isn't just making checkout easy. It's making it simple for anyone to start and run a business. It's the commerce platform behind 10% of all e commerce in the US from big names like Mattel and Gymshark to brands just starting out. If you're launching your own store, Shopify gives you a leg up from day one with hundreds of beautiful templates. No coding needed. You can manage everything in one place. Inventory, payments, analytics. Plus you've got built in marketing and email tools to help you reach new customers and keep them coming back. And that purple shop pay button. It's loved by millions of businesses around the world and delivers the best converting checkout on the planet. Your customers already trust it with Shopify. Selling online really is that easy. If you want to see less carts being abandoned, it's time for you to head over to Shopify. Sign up for your $1 per month trial and start selling today at shopify.com cold case go to shopify.com coldcase shopify.com.

[Narrator]

Coldcase On March 4, 1992, the investigative team searched the Zantras house. Here's Agent Deprima again.

[Agent Ray DePrima]

We go in this time with our forensic lab and we take the banister apart, we take up the carpet and we bring the luminol. We get this great fluorescence and we knew that we had blood.

[Narrator]

The luminal reacting to what was likely blood was a good evidence find. But they found something in the basement that directly connected Zanter to Sharon Blum. This is Sergeant Cummins again.

[Sergeant Barry Cummins]

The other search teams in the basement did locate a set of keys that were later identified as keys belonging to Sharon Bloom.

[Narrator]

Agent deprima left the house feeling like he had finally solved the case.

[Agent Ray DePrima]

As we left that day, I felt the case was solved. Got the blood, we got the keys. As it turned out, it was only the beginning.

[Narrator]

On October 23, 1992, a grand jury indicted Stephen Zanter on a charge of murder. Three years later, however, the case had still not gone to trial. Here's Agent deprima.

[Agent Ray DePrima]

His defense attorney submitted a motion to suppress the evidence, especially the keys. It went to the Minnesota Supreme Court and they threw the keys out, claiming that we had overstepped our bounds, that we didn't have probable cause to seize the keys, that we only had probable cause to seize the blood.

[Narrator]

Without the keys, the prosecution had no direct link between the blood found on the carpet and Sharon Bloom. Here's Sergeant Cummins.

[Sergeant Barry Cummins]

Basically, at that point in time, DNA was not as sophisticated as it is now. The blood evidence in the carpet had been diluted with a number of chemicals to clean the carpet. And they could say it was consistent with. But they couldn't say that it was specifically Sharon Bloom's blood.

[Narrator]

Unwilling to risk a possible acquittal, Rice County's prosecutor reluctantly dropped the charges. Sharon's boyfriend David had serious doubts about the case.

[David Cofode]

In my mind, it was never going to be carried to conclusion that might have been the conclusion. We know who did it and we know where he lives and we know how he did it and we know why he did it. And that's as far as it could ever go.

[Narrator]

By 1999, forensic technology had significantly advanced. Here's Ann Marie Gross, a forensic scientist at the Minnesota Bureau of Apprehension.

[Ann Marie Gross]

Well, we're able to do more types of samples. For example, we do cigarette butts and envelope flaps and sweat. So it kind of has opened the door to really the types of evidence that we receive.

[Narrator]

Gross was asked to look at the section of carpet pulled from Steven Zanter's home. Even though cleaning products used in the carpet had degraded the blood stains, she was still able to create a genetic profile.

[Ann Marie Gross]

The blood then on the carpeting matched the DNA profile from the blood of the victim.

[Narrator]

In addition to the blood evidence, a hair found at the body dump site was linked through DNA to samples provided by Steven Zanter. Faced with the physical evidence, Zanter confessed to the crime in April of 2003 and was sentenced to 25 years at Minnesota's Stillwater Penitentiary. For Sharon Bloom's family and friends, the sentence came with mixed emotions.

[David Cofode]

I've never met someone without a conscience until I met Mr. Zander. And I. I've been brought up to not believe in revenge and to believe in justice. And if this was the justice then I will have to accept doesn't mean that I sometimes feel it still falls short.

[Narrator]

Cold Case Files the podcast is hosted by Brooke giddings, produced by McKamey Lin and Steve Delamater. Our executive producers are Jesse Katz and Ted Butler. Our music was created by Blake Maples. This podcast is distributed by Podcast one. The Cold Case Files TV series was produced by Curtis Productions and is hosted by Bill Curtis. You can find me brookeginnings on Twitter and brookthepodcaster on Instagram. I'm also active in the Facebook group Podcast for Justice. Check out more Cold case [e-mail] or learn more about cases like this one by visiting the A&E RealCrime [e-mail] RealCrime.

[Pluto TV Announcer]

This October, Fear is free on Pluto TV. With horror movie collections from Paranormal Activity.

[Investigator Hines]

The Ring, you will die inside seven.

[Pluto TV Announcer]

Days Scream and from Dusk till Dawn.

[Sergeant Barry Cummins]

This is my kind of place.

[Pluto TV Announcer]

And don't miss the man made nightmares in Mary Shelley's Frankenstein or the world ending chaos in 28 days later.

[Sponsor Voice]

There's something in the blood.

[Pluto TV Announcer]

All the scares, all for free. Pluto TV stream now pay Never.