Jim Lane, a Fort Worth attorney who is representing Dean, declined to comment on the case.
The 28-year-old woman was playing video games with her nephew in the back bedroom of the home when they heard noises coming from outside, the document says.
She then pulled her handgun from her purse, her nephew told police, and raised it. She was pointing it toward the window when she was shot and fell to the ground.
It’s unclear how much time passed before Jefferson was shot or whether the nephew heard the officer’s voice.
The former officer is not cooperating with detectives
Dean has declined to speak with investigators since Saturday, the warrant states.
He first refused to be interviewed by the detectives in the immediate aftermath of the shooting, and his attorneys told police that he was going to provide a written statement at a later date, according to the document.
In most police shootings, officers give an oral or written statement about what happened for an internal investigation, either immediately after the shooting or within 72 hours.
As Dean resigned from his job at the police department on Monday, he also declined to provide a written statement, the affidavit states.
Speaking to reporters on Tuesday, Interim Police Chief Ed Kraus confirmed that Dean has not been cooperating.
“I cannot tell you what he felt. He did not give a statement,” Kraus said.
Other responding officer could not share many details
The second officer responding to Jefferson’s home, Officer C. A. Darch, was with Dean when he went into the backyard.
During the shooting, Darch could only see Jefferson’s face through the window because Dean was standing between her and the house, the warrant said.
Body camera video shows Dean approaching the window and firing a single shot but it doesn’t show Darch within eyesight of her colleague.
CNN is attempting to reach Darch for comment.