Ex-Dallas police officer Amber Guyger broke down on the witness stand Friday, repeating “I’m so sorry.” 

She said the fatal shooting of her upstair's neighbor on Sept. 6, 2018 continually haunts her.

The former Dallas officer was the first witness called to the stand by the defense after the state rested their case the day before. Charged with murder, she faces up to 99 years in prison. 

“I feel like a piece of crap,” Guyger, 31, testified. “I hate that I have to live with this every single day, and I ask God for forgiveness and hate myself every single day.”

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'I had no idea where I was'

Guyger told investigators that she had just ended a 13-hour shift when she parked on the fourth floor and mistook Jean's apartment, located one floor above her third-floor unit, as her own, records show. 

On the stand Friday, she said she was "just ready to go home" when asked about her mindset as she walked down the hallway at the South Side Flats apartments that night.

Guyger broke into tears as she described the moment she got to the door, which she was able to open because of a defect that left it unlocked.

“The force of me putting the key in opened it,” Guyger later testified.

With the door slightly ajar, she said, she could hear the sound of movement inside. Then she saw “a silhouette of a figure," who she believed was an intruder.

Standing just inside the doorway, she testified that she pulled out her handgun and hollered, “Let me see your hands! Let me see your hands!”

But she said the figure came toward her, “coming at a fast-paced walk.” She said he was yelling, “Hey! Hey! Hey!”

That's when she fired at him.

"I thought he was going to kill me," she said. 

Guyger said she fired two shots. One of those shots went through Jean's chest and pierced his heart.

She said she then realized she was in the wrong apartment. Guyger said she knelt beside Jean, applied pressure to his wound with one hand and called 911 with the other.

"I had no idea where I was,” she said. 

Guyger testified she was so disoriented that she had to walk outside of the unit to get the apartment number for the 911 dispatcher.

"I thought it was my apartment," she repeated over and over again on the 911 call. "I didn't mean to. I didn't mean to."

While speaking with the 911 operator, Guyger testified that she realized: "I shot an innocent man who didn't deserve it." 

“I wish he was the one with the gun and had killed me,” Guyger told the court Friday. “I never wanted to take an innocent person’s life. And I am so sorry.”

'Can you imagine Mr. Jean's perspective?'

During cross-examination, prosecutor Jason Hermus accused Guyger of being more focused on herself than on Jean, the victim. 

The prosecutor asked Guyger to recall her earlier testimony in which she said being alone in the apartment with a wounded Jean was the "scariest thing" she could imagine.

"Can you imagine Mr. Jean's perspective?" he said. "An intruder barging into his apartment?"

"So that would probably be the scariest thing you could imagine?" he added. 

Hermus then asked Guyger about two text messages she sent her former police partner, Martin Rivera, as Jean lay wounded on the floor and before officers arrived at the scene. 

Guyger and Rivera were previously involved in a sexual relationship. She texted Rivera that night telling him, "I need you. Hurry up!" And a minute later, "I f----d up."

The prosecutor also asked Guyger about messages she sent to Rivera two days after the shooting that were sexually flirtatious and talked about "getting drunk."

Hermus then questioned Guyger about her failure to stay inside the apartment and provide CPR. 

"I wanted somebody there fast to give him help," she told Hermus when asked why she went out into the hallway.

"You knew how to do CPR properly?" Hermus asked the former officer.

"I've never done it on a person," she replied.

But Hermus hammered back, asking her once again if she was properly trained to do CPR.

"Yes, we were," she said.

"Did you properly perform CPR on Mr. Jean?" Hermus asked.

"No, I did not," she replied.

"But you could have, right?" the prosecutor said.

"I tried to do a little CPR," she replied.

“Why would you try to do 'a little CPR' on a man who is dying and needs your full attention?" he asked. 

Hermus also raised questions about Guyger’s decision to pull her gun and enter the apartment, rather than call for back-up.

“You could have taken a position of cover and concealment, and backed off,” Hermus said.

The prosecutor then asked Guyger why she didn't use the combat gauze and a first- aid kit that was inside a backpack she was carrying at the time.

"Is there a reason why you didn't use this stuff right here, which is designed to control traumatic bleeding?" Hermus asked as he pulled out contents from the kit.

"It never crossed my mind," she said.

Hermus questioned Guyger's motives during the shooting.

“All this talk about a sad mistake, when the rubber meets the road, you intended to kill Mr. Jean,” Hermus said.

“He (Jean) was the threat, yes sir,” Guyger responded.

“You intended to kill Mr. Jean?” Hermus asked.

“I did,” Guyger testified.  

More day 5 testimony

Guyger’s testimony was the most important element of her defense team’s presentation, but her lawyers presented a host of other testimony to jurors to persuade them that the shooting was a tragic mistake, and not murder.

Jurors heard from two Department of Public Safety special agents that witnessed apartment doors not closing properly when they went to the South Side Flats to talk with residents.

The defense also called several witnesses who, like Guyger, told jurors they had parked on the wrong garage floor. 

One witness, a Dallas attorney, told jurors that he made it all the way into an apartment, startling a woman who was sitting on a couch in the living room before he realized he didn’t live there.

The judge dealt the defense two defeats late Friday. 

During hearings outside the presence of the jury, Judge Tammy Kemp ruled that a crime scene reconstruction expert’s testimony was too vague to be helpful to jurors. 

She also ruled that Texas Ranger David Armstrong, the lead investigator in the case, could not tell jurors that, in his opinion, Guyger broke no laws in the shooting.

Because the jury is sequestered, the judge is wasting no time in the trial. Testimony continues Saturday from 9 a.m. to 4 p.m.

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