Mollie Tibbetts' murder: A complete timeline of events

On July 18, 2018, Mollie Tibbetts, a 20-year-old University of Iowa student, vanished while jogging near her boyfriend's house in Brooklyn, Iowa. Her disappearance triggered a month-long investigation involving local authorities, the FBI, and volunteers, with hundreds of leads and surveillance footage reviewed.

As per People's report dated August 21, 2018, Mollie Tibbetts' last known activity included a Snapchat sent around 10 pm on the night of her disappearance. However, she failed to report to work the following morning, prompting her family to report her missing.

According to an ABC News report dated August 6, 2018, investigators initially explored digital trails from Mollie Tibbetts' Fitbit and phone data, leading to surveillance that captured a black Chevy Malibu following her. This vehicle was later linked to Cristhian Bahena Rivera, who confessed to encountering Tibbetts that night. On August 21, 2018, Rivera led authorities to her remains in a cornfield.

As per the KCRG report dated August 23, 2018, the cause of death was ruled as multiple sharp force injuries. The case is also explored in Dateline NBC's season 33, episode 22, titled The Last Mile, airing on April 6, 2025, at 10/9c.

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Mollie Tibbetts's timeline explored with key events leading to her murder

The case of Mollie Tibbetts, a 20-year-old University of Iowa student, unfolded over several weeks in the summer of 2018 and involved a nationwide search effort that ultimately ended in finding her dead body.

Tibbetts was last seen jogging in Brooklyn, Iowa, around 7:30 pm on July 18, 2028. She was staying at her boyfriend Dalton Jack's home and dog-sitting while he was out of town. Jack told ABC News that he received a Snapchat from her at around 10 pm that night, though the exact time the message was sent remains unclear.

According to the KCRG report dated May 17, 2021, her absence was first noticed the following morning when she failed to show up at her job at a daycare center.

After her family reported her missing on July 19, 2018, law enforcement agencies, including the Iowa Division of Criminal Investigation and the FBI, launched a coordinated search across Poweshiek County.

Hundreds of volunteers joined the efforts, and investigators gathered digital evidence from Mollie Tibbetts' Fitbit and cellphone, as stated in an ABC News report dated August 6, 2018.

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Search intensifies and digital leads emerge

In the weeks that followed, tips were poured in, and multiple locations were searched, including a pig farm near Guernsey. Investigators analyzed video surveillance footage and eventually spotted a black Chevy Malibu appearing to follow Tibbetts during her jog. According to The Gazette report dated May 18, 2021, the vehicle was traced back to Cristhian Bahena Rivera, a local farmhand.

Rivera was brought in for questioning in August 2018. Initially denying involvement, he later admitted to encountering Tibbetts, claiming she threatened to call 911, after which he "blacked out." As per a People report, Rivera led authorities to a cornfield where Tibbetts' body was found on August 21, 2018, covered in corn stalks.

The Iowa State Medical Examiner determined the cause of death to be "multiple sharp force injuries" as per Oxygen.

Rivera was charged with first-degree murder the following day. During his trial in May 2021, his account changed. He alleged that two masked men had coerced him into driving and later placed Tibbetts' body in his trunk.

However, this claim was dismissed due to inconsistencies and the weight of physical evidence, including blood in his vehicle that matched Tibbetts' DNA.

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Trial and sentencing

Rivera's trial didn't happen right away. It faced several delays, first from legal motions and then from the COVID-19 pandemic. Jury selection finally kicked off on May 17, 2021. After ten days in court, the jury came back with a verdict on May 28.

They found him guilty. A few months later, on August 30, 2021, the judge handed down a life sentence with no chance of parole. In Iowa, that's the standard punishment for first-degree murder.

Laura Calderwood, Mollie Tibbetts's mother, remembered the moment investigators told her they had found her daughter. She had to break the news to the rest of the family.

As per NPR, on August 31, 2021, Tibbetts' mother, Laura Calderwood, addressed the court during sentencing. She said:

“Because of your actions Mr. Rivera, I will never get to see my daughter become a mother.”

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To learn more about Mollie Tibbetts' case, watch the upcoming episode of Dateline NBC, The Last Mile, which airs on April 6, 2025, at 10/9c.