Key takeaways from Day 2 of trial for accused killer of University of Iowa student Mollie Tibbetts

A law enforcement investigator testified on Thursday that it was only by chance that he scored the biggest break in the 2018 disappearance and slaying of University of Iowa student Mollie Tibbetts.

Poweshiek County, Iowa, sheriff's deputy Steve Kivi testified that he was driving home on Aug. 16, 2018, when he spotted a black Chevrolet Malibu matching the description of a vehicle of interest in the case of the missing 20-year-old student.

Kivi said he jotted down the license plate and followed the car until it stopped and the driver got out.

"I said, 'Hey, can I talk to you for a second?"' Kivi testified of his initial contact with the driver.

The driver turned out to be Cristhian Bahena Rivera, a 26-year-old farmworker now on trial in Scott County, Iowa, on a first-degree murder charge in the slaying of Tibbetts. He has pleaded not guilty.

Kivi said that just two days before his encounter with Bahena Rivera, an undocumented immigrant from Mexico, other investigators on the case were combing through security video they had collected from homes and businesses in Brooklyn, Iowa, and came upon footage of Tibbetts jogging in the rural farming community. Investigators also noticed in the footage that a black Chevy Malibu with chrome side mirrors and chrome door handles kept appearing over and over again in the same area and around the same time Tibbetts was out exercising.

Kivi said that when he first asked him about Tibbetts, Bahena Rivera denied having "any knowledge that would be useful to us."

Under cross-examination from defense attorney Chad Frese, Kivi said Bahena Rivera "seemed calm, not nervous." He said Bahena Rivera provided him with a birth certificate confirming his name and that he said he worked at a dairy just outside Brooklyn.

Kivi testified that prior to his first contact with Bahena Rivera, investigators had received no tips or intelligence pointing to Bahena Rivera as a possible suspect or that a Hispanic man was involved in Tibbetts' disappearance.

At that time, he said investigators had spent a month searching for Tibbetts, who went missing on July 18, 2018, and that the investigation had chased down numerous leads that led them to dead ends.

Video recorded Tibbetts jogging

Agent Derek Riessen of the Iowa Division of Criminal Investigation testified he and other investigators were going through about 30-days worth of video taken from the home of Brooklyn resident Logan Collins, 27. Collins testified that he turned over to authorities in mid-August 2018 video taken from four security cameras he had mounted on his garage.

Riessen said that one of Collins' cameras captured a person jogging in a distance around 7:45 p.m. on the day Tibbetts went missing.

"I looked at it numerous times," Riessen said. "I can say it was a runner, [who] had a ponytail."

He said investigators determined the jogger seen in the video was Tibbetts, testifying that another witness had seen Tibbetts jogging not far from Collins' home just before she went missing.

"What we decided to do is start logging everything we saw on the video: vehicles, pedestrians, anything in and around that area prior to 7:45 and also after 7:45," Riessen said.

Riessen said a black Mailbu was seen going past Collins home six different times and that the last time it was seen it was headed in the direction Tibbetts was running.

"We wanted to know who was driving the vehicle to determine if they had seen Mollie," Riessen said.

Suspect question further

Acting on the information Kivi had gotten from Bahena Rivera, Special Agent Michael Fischels of the Department of Homeland Security said he and other investigators went to the dairy where Bahena Rivera worked on Aug. 20 and questioned him and other employees with the permission of the dairy owners.

Fischels said Bahena Rivera again denied any knowledge of Tibbetts' disappearance but allowed investigators to take a DNA sample and fingerprints and gave them permission to search his car and home.

"He agreed to come down to the sheriff's office and continue the interview," Fischels said.

Under cross-examination from Frese, Fischels testified that Bahena Rivera's boss offered to have the company's attorney accompany him to the interview.

"I told him he didn't need the company attorney," Fischels testified.

'Mr. Rivera said that he got angry'

Pamela Romero, a former Liberty City, Iowa, police officer, said she was asked to help interview Bahena Rivera because she speaks Spanish.

Romero said that during an 11-hour interview, Bahena Rivera confessed when he was confronted with a still image of his car captured on Collins' security camera.

Romero, who now works for a turkey processing factory in Iowa, said Bahena Rivera allegedly told her that he spotted Tibbetts jogging, waved at her, and that she smiled and waved back. He allegedly said, according to Romero, that he found Tibbetts "hot" and decided to follow her.

She said Bahena Rivera was given numerous breaks during the interview, offered food and something to drink.

She said the interview continued into the early morning hours of the next day, Aug. 21, and that Rivera went with her and other investigators to his home, his place of work and then directed them to a cornfield on the outskirts of Brooklyn.

Romero said that while sitting in a police vehicle parked near the cornfield, she read Bahena Rivera, who had been placed under arrest, his Miranda rights. He said he waived his right to remain silent and agreed to continue the interview.

"I asked Mr. Rivera to give me all the details that he could remember," Romero said. "He told me he saw her running three times. One of those times he parked his car and ran after her, or jogged after her, came close to her that she noticed him."

Romero said Bahena Rivera allegedly claimed Tibbetts said she was going to call the police.

"Mr. Rivera said that he got angry," Romero said. "After he said that he got angry, he stated that they started fighting. He said that Mollie tried to slap him and was screaming at him."

Romero said that Bahena Rivera allegedly claimed that when he gets angry, he usually blacks out.

"So the next thing that he told me was he remembered driving and looking down to his legs and finding the earbuds that belonged to Mollie and that is when he remembered he had Mollie in the back of his vehicle, in the trunk," Romero said. "He stated that he did not remember putting her inside the car. He did not remember how she got there but he did remember how he took her out of the vehicle."

Romero said Bahena Rivera allegedly said he drove to the cornfield, opened the trunk and saw blood on Tibbetts' neck.

During his opening statement at the trial on Wednesday, prosecutor Bart Klaver told the jury that an autopsy determined Tibbetts was stabbed seven to 12 times in the neck, head and chest.

"He told me that he took her out of the car, put her on top of his shoulder, carried her into the cornfield, laying her down, covering her with corn leaves and leaving right away," Romero said.

Romero testified that when she pressed Bahena Rivera for more details, he allegedly replied, "I brought you here, didn't I? So, that means that I did it. I don't remember how I did it."