Dallas County prosecutor Jason Hermus said Monday that former Dallas Police officer Amber Guyger ignored clear signs that she was on the wrong floor while she walked to 26-year-old Botham Jean’s doorstep, entered his apartment and fatally shot him.

Guyger’s trial began Monday afternoon in the Dallas County 204th District Court, and she is charged with the murder of Jean, whom she fatally shot on Sept. 6, 2018.

Guyger allegedly entered an apartment she thought was hers after finishing a shift, when she saw a large silhouette, according to a previous Shorthorn article. Guyger claimed she thought a burglar was inside the apartment. According to the article, she said she then drew her firearm, gave verbal commands that were allegedly ignored and shot her gun two times.

One bullet struck Jean in the torso, and he was taken to Baylor Hospital, where he died. She called 911 from her cell phone after discovering she was not at her apartment.

She was arrested Sept. 9, 2018, on a manslaughter charge, but she was later indicted on a murder charge.

Guyger’s defense attorney said because the complex that she lived in at the time, South Side Flats, was confusing, she accidentally entered Jean’s apartment. Her defense said the numbers of the apartment floors were not clearly marked, and the hallways, entrances and lights looked identical. These similarities, coupled with her being tired, caused her to not pay attention as she entered, he said.

From fall 2012 to spring 2013, Guyger was enrolled at UTA but did not obtain a degree, according to a previous Shorthorn article. Her intended major was criminology and criminal justice.

On the day of the murder, Guyger had been on the phone and texting Dallas Police Officer Martin Rivera, whom she had a sexual relationship with, Hermus said.

At 9:38 p.m., Guyger and Rivera began a 16-minute conversation on the phone that continued until she arrived home, Hermus said. She drove into her gated community, into the parking garage, but before she parked, Guyger pulled over to give Rivera her full attention, he said.

“Whatever the conversation was with her and Martin Rivera required her to pull off the lane of traffic in her parking garage and give him full attention,” he said.

Rivera only recalled that they spoke about what happened after he left work. Hermus said he believes that there’s something more to that conversation.

“She was operating like a normal person,” Hermus said. “After this conversation with Martin Rivera, there was a marked difference.”

That conversation ended at 9:55 p.m., and Guyger got back into the lane of traffic, he said. She parked in the fourth floor where the garage is in open air, while the third floor is closed in.

But Guyger’s defense said it was dark outside, and she didn’t inspect her surroundings, and everything looked the same.

Hermus said the fourth floor has differences compared to Guyger’s floor.

Her neighbor has a decorative planter, he said, and that night it wasn’t there because Guyger was on the wrong floor. For the last two months, at least twice a day Guyger has seen and walked past that planter.

Guyger had no floor mat outside her apartment, but Jean did, and it was bright red, he said. She had to step on the “obvious” mat to get inside, he said.

All of these incidents could be explained away in isolation, but all together are incriminating, he said.

Guyger was operating on autopilot, the defense said. When she got home, she drove through the parking garage, didn’t count the floors and parked in the spot that was close to the entrance.

“Was it evil of her not to count the floors?” the defense asked.

Guyger’s defense attorney said investigators interviewed and learned that 93 tenants parked in the wrong floor unintentionally, 76 of which lived on the third and fourth floors.

When Guyger got out of her car, she had her gear, her heavy vest and her bag in the left hand, the defense said. She didn’t pay attention to the floor mats on her floor or her neighbors planter.

“She’s worked a long day,” the defense said. “She’s tired — she’s almost home.”

Judge Tammy Kemp oversees the case and said the court will reconvene at 8:30 a.m. on Tuesday.

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