Dateline NBC: The Last Mile
Host/Author: NBC News
Release Date: June 3, 2025

Introduction

In the gripping episode titled "The Last Mile," Dateline NBC unravels the harrowing true-crime mystery of Molly Tibbets, a 20-year-old University of Iowa freshman who vanished under mysterious circumstances. This detailed account chronicles the relentless search, investigative breakthroughs, and the eventual resolution of Molly's disappearance, offering listeners an in-depth look into a case that captivated a community and drew national attention.

Molly Tibbets: A Beloved Young Woman

Molly Tibbets was a vibrant and beloved young woman whose life was tragically cut short. Described by her cousin, Morgan Collum, as "a ball of sunshine to be around" (01:04), Molly was not only an honors student but also a dedicated cross-country runner and a natural with children, excelling in her role at a local summer day camp. Her enthusiastic participation in activities, such as pranking coworkers and maintaining a "6002" Snapchat streak with Morgan, highlighted her joyful and lively personality.

The Disappearance: A Normal Evening Turned Nightmare

On July 18, 2018, Molly's routine evening took a dark turn. After a productive day at work, she stayed over at her boyfriend Dalton Jack's house before embarking on her regular evening jog. However, that night was different. Despite sending a Snapchat message to Dalton and informing her mother of her plans, Molly never returned. As days passed without any contact, alarm bells rang throughout her close-knit community of Brooklyn, Iowa.

Morgan Collum recalls the overwhelming panic: "I checked my phone and I saw I had a missed call from my dad, I had a missed call from my brother. I had a missed call from my Aunt Laura. And I just knew in that moment, this isn't good" (06:26). The community mobilized, with volunteers and law enforcement intensifying their search efforts along the "blacktop" road where Molly was last seen jogging.

Initial Investigation: Building the Timeline

Special Agent Trent Valletta and Deputy Steve Kivi spearheaded the investigation for Iowa's Division of Criminal Investigation and Powasheek County Sheriff's Office, respectively. Their primary focus was to reconstruct Molly's movements from the evening she disappeared (02:36).

Key discoveries included:

• Security Camera Footage: A home security camera captured Molly jogging on the "blacktop" at approximately 7:48 PM (25:09), providing a crucial timestamp.

• Cell Phone and Fitbit Data: Investigators cloned Molly's missing phone using her password, revealing her location and activity patterns. Additionally, her Fitbit was analyzed to determine her running routes, though it did not provide new leads (17:43).

Despite extensive searches covering road ditches, fields, and waterways, initial efforts yielded no substantial findings, leading investigators to explore potential personal issues Molly might have been facing. However, her impeccable reputation left little to go on.

Breakthrough: The Black Chevy Malibu

A pivotal moment in the investigation occurred when Deputy Steve Kivi identified a distinctive black Chevy Malibu on security footage just minutes after Molly was last seen. The vehicle's unique aftermarket modifications, including custom mirrors and chrome accents, made it stand out despite the grainy footage (26:20).

As Deputy Kivi pursued leads, he encountered the same black Malibu on Highway 63, leading to a critical interaction with Christian Behina Rivera, an undocumented worker at a local dairy farm. Rivera's demeanor during the initial conversation was cooperative yet nonchalant (30:22), but inconsistencies in his story raised suspicions.

Interrogation and Confession

Officer Pamela Romero, inexperienced in such high-stakes interrogations, conducted the questioning of Rivera. Initially maintaining a light and conversational tone, Romero gradually pressed Rivera for more information regarding his sighting of Molly (32:34).

Rivera eventually admitted to seeing Molly and disclosed that he had driven past her multiple times, leading investigators to a cornfield where Molly's remains were discovered shortly before sunrise (37:07). Rivera's confession was pivotal, although it faced legal challenges when an incomplete Miranda warning led to the exclusion of part of his initial confession. Fortunately, a subsequent Miranda warning preserved the integrity of his second confession, which, coupled with DNA evidence from blood found in his car, solidified the case against him.

Legal Proceedings and Conviction

Three years after the disappearance, Rivera stood trial for the first-degree murder of Molly Tibbets. Despite efforts to recant his initial confession, the prosecution presented a strong case built on multiple pillars:

1. Security Footage: Confirmed the presence of Rivera's black Malibu near the time and location of Molly's disappearance (29:19).

2. DNA Evidence: Blood matching Molly was found in Rivera's vehicle (40:04).

3. Confession: Rivera’s admission of involvement, obtained after proper Miranda warnings, underscored his culpability (37:20).

The jury found Rivera guilty of first-degree murder, sentencing him to life in prison without the possibility of parole. Morgan Collum reflected on the verdict: "It's good to know that at least justice has been served in the way that it can" (42:17).

Aftermath and Legacy

Molly Tibbets’ tragic death left an indelible mark on her family, friends, and the broader community. In her memory:

• Commemorative Ribbons: Each year, teal ribbons, Molly's favorite color, are displayed around the time of her disappearance.

• Memorial Fund: A fund for child and adolescent psychiatry at the University of Iowa has raised over half a million dollars in her honor.

• Personal Tributes: Morgan Collum continues to honor Molly by participating in running events, embodying her spirit and dedication (43:31).

Molly's legacy serves as a poignant reminder of the impact one individual can have on a community and the enduring quest for justice.

Conclusion

"The Last Mile" encapsulates the relentless pursuit of truth and justice in the face of tragedy. Through meticulous investigation, community solidarity, and unwavering determination, the episode highlights both the challenges and breakthroughs inherent in solving true-crime cases. Molly Tibbets' story stands as a testament to resilience and the enduring hope that justice will prevail.

For more detailed moments and emotional reflections from those involved, listeners are encouraged to tune into the full episode of Dateline NBC's "The Last Mile."

Notable Quotes

• Morgan Collum (06:26): "I just knew in that moment, this isn't good."

• Deputy Steve Kivi (25:42): "Is this it? Is this the break we needed?"

• Officer Pamela Romero (37:07): "So he said he saw her. Molly smiles at him, and then he decides to park his car, like, 100ft behind her."

• Morgan Collum (42:22): "There's not a day, I think, where I don't either think of her or just feel her."

Timeline of Key Events

1. 7:00 PM: Molly sends text message about going for a jog after dinner (07:53).

2. 7:48 PM: Security camera captures Molly jogging on the blacktop (25:09).

3. 7:49 PM: A black Chevy Malibu passes shortly after Molly (25:50).

4. 8:02 PM: The Malibu is seen on camera again, heightening suspicions (34:17).

5. 8:53 PM: Molly's phone signal dies 15 miles southeast of Brooklyn (20:25).

6. 8:00 AM (Next Day): Extensive volunteer search efforts begin (12:45).

7. Day 33: Rivera's initial confession leads investigators to the cornfield (37:07).

8. Trial and Conviction: Three years later, Rivera is convicted of first-degree murder (41:58).

Key Takeaways

• Community Effort: The collective response from Molly’s family, friends, and volunteers was instrumental in maintaining momentum in the search.

• Technological Advances: The use of cell phone cloning and Fitbit data exemplifies the role of technology in modern investigations.

• Critical Investigation Moments: Identifying the black Chevy Malibu was a turning point, demonstrating how small details can lead to significant breakthroughs.

• Legal Procedures Matter: Proper adherence to Miranda warnings proved crucial in securing a lawful conviction, underscoring the importance of protocol in criminal investigations.

• Lasting Legacy: Molly’s story continues to inspire and remind communities of the importance of vigilance, support, and perseverance in the face of tragedy.

Dateline NBC expertly weaves together the emotional journeys of those involved and the meticulous steps taken by investigators to bring justice for Molly Tibbets. "The Last Mile" stands as a compelling narrative of loss, determination, and the unyielding pursuit of truth.