A murder warrant for Aaron Dean, the Fort Worth officer who killed Atatiana Jefferson in her home, recounts what led up to the shooting from the perspective of her 8-year-old nephew.

Aaron Dean was arrested Monday and quickly released on $200,000 bond. (Tarrant County Jail) (Tarrant County Sheriff's Dept.)

The boy, who was in the room with Jefferson when she was shot, told a forensic interviewer that he and his aunt were playing video games together about 2:30 a.m. Saturday when she heard noises outside their home in the 1200 block of East Allen Avenue.

Jefferson, 28, took her handgun from her purse and pointed it “toward the window” before she was shot, the nephew said, according to the arrest-warrant affidavit.

The 8-year-old saw his aunt fall to the ground. She was pronounced dead at 3:05 a.m.

Interim Police Chief Ed Kraus said at a news conference Tuesday that it “makes sense that she would have a gun if she felt that she was being threatened or there was someone in the backyard.”

That sentiment was echoed by an attorney for the victim’s family. Lee Merritt said Jefferson had every right to defend herself because the officers did not announce themselves as law enforcement.

“It’s only appropriate that Ms. Jefferson would have a gun,” Merritt said, noting that she had a license to carry the legally owned firearm. "When you think there’s someone prowling around in the back at 2 in the morning, you may need to arm yourself. That person could have a gun.”

Civil rights attorney Lee Merritt, the lawyer for the Jefferson family, discusses city leaders' reactions to the deadly shooting of Atatiana Jefferson.

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Merritt accused the Fort Worth Police Department of providing a defense for Dean by writing that Jefferson had pointed a gun at the window before Dean fired.

“Suddenly, they’re building the defense in the arrest warrant itself for the officer, alleging that Atatiana pointed a weapon out of the window,” the lawyer said.

The warrant doesn’t say Dean told police he saw a weapon, but it does say his partner could only see Jefferson’s face in the window before Dean opened fire.

Fort Worth Mayor Betsy Price, speaking at a news conference Monday, said the gun was irrelevant.

“She was in her own home,” the mayor said of Jefferson. “She was taken from her family in circumstances that are truly unthinkable.”

Kraus said previously that the department’s decision to release a still image of the firearm found in the room where Jefferson was shot — without any further information about the weapon or what it had to do with the case — wasn’t the right call.

Anastasia Gonzalez of Burleson leaves flowers on the front sidewalk of Atatiana Jefferson's home on E. Allen Ave in Fort Worth. In the wake of Fort Worth police officer Aaron Dean shooting and killing Jefferson in her home, people have been leaving flowers at the scene. (Tom Fox / Staff Photographer)

Dean, 34, was arrested at his attorney’s office about 6 p.m. Monday on a murder charge. He was freed from the Tarrant County Jail after posting $200,000 bond shortly after 9 p.m., court records show.

Jim Lane, a Fort Worth attorney representing Dean, told KXAS-TV (NBC5) that the situation is a tragedy and that his client is sorry.

Kraus, who spoke before the affidavit was released, said it’s still unclear what Dean was thinking when he shot through a bedroom window, striking Jefferson.

That’s because the former officer, who resigned Monday, has not provided a written statement nor answered any questions, the chief said. Kraus had been prepared to fire the officer Monday morning, but Dean quit before he could.

Dean and another officer had been called about 2:30 a.m. Saturday to Jefferson’s mother’s home. A neighbor had called a non-emergency line to report that the home’s lights were on and its doors open.

The arrest-warrant affidavit for Dean released by police Tuesday said the glass storm doors to the house were closed, but the front and side interior doors were open. Officers peered into the residence through the storm doors but did not see anyone, and they did not announce their presence, according to the affidavit.

In body-camera footage of the shooting, Dean walks around in the backyard of the home. About a minute and a half into the recording released by Fort Worth police, Dean swivels toward a window, shouts at Jefferson to put up her hands and shoots her, all in a matter of seconds.

The chief said the shooting has been trying for the department.

Speaking at a news conference Tuesday, Police Chief Ed Kraus asked that the public not judge his department on the actions of one officer: "There’s absolutely no excuse for this incident.” (Tom Fox/Staff Photographer) (Tom Fox)

Kraus choked up as he likened the aftermath of the shooting to ants working to build an anthill, when “somebody comes with a hose and washes it away and they just have to start from scratch.”

“We have a great many officers who work extremely hard every day,” Kraus said. “I ask you please do not let the actions of one officer reflect on the other 1,700. There’s absolutely no excuse for this incident.”

The family’s attorney and Jefferson’s siblings spoke at a news conference Tuesday in Dallas, where they demanded that the system be held accountable for the shooting, not just the officer.

“This rookie cop is not going to be the scapegoat for what happened. Yes, he’s going to take his punishment, but the system failed him,” said Jefferson’s brother, Adarius Carr. “Whoever sent him out failed him. The training failed him. There’s a lot that has to get fixed. The city failed him.”

Merritt called on the department to explain “who put this family in this predicament.”

“This one officer obviously did something terrible and tragic, but this was a breakdown from the top to the bottom,” he said.