DALLAS — Story has been updated throughout after full day's testimony.

Former Dallas police officer Amber Guyger reasonably believed she was shooting an intruder in her apartment when she shot and killed 26-year-old Botham Jean, the lead investigator of the case said Wednesday. 

Guyger, 31, is charged with murder in the death of her upstairs neighbor. She was off duty but still in uniform when she mistakenly went to Jean’s apartment instead of her own. She was able to get inside because the door was unlocked and not properly latched. 

Defense attorneys say Guyger shot Jean in self-defense believing he was an intruder advancing on her when she entered the apartment. 

Texas Ranger David Armstrong said Wednesday that he doesn’t believe Guyger committed any crime, including murder, manslaughter or criminally negligent homicide.

“I believe that she did perceive him as a deadly threat,” Armstrong said. “I don’t believe it was reckless or criminally negligent based on the totality of the investigation.”

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But jurors won’t get to hear that. 

The Texas Rangers issued an arrest warrant for Guyger on a manslaughter charge in the days after the shooting, despite what Armstrong believed. She was later indicted on the murder charge. 

The jury was outside the courtroom when defense attorney Robert Rogers questioned Armstrong, who was called to the witness stand by prosecutors. Armstrong testified briefly Tuesday afternoon and was still on the stand when court resumed Wednesday. 

Rogers wanted to question Armstrong about his opinions on whether Guyger reasonably believed she was in her own apartment and where he believed Jean was standing when he was shot. 

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Jean had been sitting on his couch eating vanilla ice cream topped with crumbled cookies watching TV moments before the shooting. Prosecutors allege Jean was barely getting up from the couch when Guyger walked into his home and shot him. 

Defense attorneys say he was walking toward Guyger when she shot. 

Body-camera footage showing the first officers arriving in the apartment captured images of the still-alive Jean with his head near the end of his couch and his feet in between the living room and kitchen area. His sandals appeared to have fallen off his feet. 

State District Judge Tammy Kemp re-watched the footage to see whether Armstrong could testify about his opinions on where Jean was standing when he was shot. 

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Armstrong said he believed Jean was shot standing in the position where his sandals were found. 

Jean’s family was still in the courtroom when the video was played. They had left the courtroom Tuesday before it was played for jurors. 

Jean’s father, Bertram Jean, put his head against the wall and put his hands over his ears. Allison Jean, Botham Jean’s mother, hung her head for several minutes before the couple got up to leave the courtroom. 

Allison Jean could barely contain her sobbing as she left the courtroom. 

Kemp looked up in surprise after realizing the family was in the room. 

“Oh, I’m so sorry,” she said. 

The courtroom could occasionally hear wailing outside whenever the door opened. 

Prosecutor Jason Hermus argued that Armstrong’s testimony was “inappropriate.” He said the jury has to decide for themselves whether the shooting was reasonable. 

Kemp decided defense attorneys could not question Armstrong about whether he thought the shooting was reasonable and said she doesn’t believe anyone could conclusively say where Jean was when he was shot based on the body-camera footage. 

Several officers were gathered around Jean, and Kemp said that movement could’ve pushed the sandals around. 

It's possible the jury could hear from Armstrong again if defense attorneys are allowed to recall him as an expert witness.

The Jean family returned before the jury was brought back into the courtroom.

Jean died from devastating injuries to his organs that would've caused a lot of internal bleeding, testified a Dallas County medical examiner. 

He was shot in the left side of his chest and the bullet clipped his heart, traveled downward through the left side of his lung, went through his diaphragm, stomach and intestines before stopping inside his body. 

"I would expect that it would be painful," said Dr. Chester Gwin.

Hermus demonstrated for jurors how the bullet would've traveled downward through Jean's body. 

Guyger is 5-foot-3. Jean was 6-foot-1. 

To fire a shot that traveled downward through Jean's body, Guyger would've had to have stood taller than him. Prosecutors allege Jean was still sitting on the couch when he was shot. Defense attorneys say he was walking toward Guyger and then crouched down. 

Testimony will continue at 8:30 a.m. Thursday. 

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