FORT WORTH (CBSDFW.COM) — The first major legal arguments started Monday in the murder case against former Fort Worth police officer Aaron Dean.

Dean’s defense team spent hours going through motions filed in 2020, asking the state for dozens of materials it may have uncovered as it prepared for the case, including disciplinary records for more than 150 police officers, video from city cameras and the contents of any database that may have details on the case.

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Judge David Hagerman is also expected to hear Dean’s request to delay the trial from its scheduled January start, and move it out of Fort Worth due to pre-trial publicity over the case.

Dean faces a murder charge for killing Atatiana Jefferson in October 2019. He was dispatched to a call about an open door at her mother’s house where she was staying, but never identified himself and shot Jefferson when he saw her inside with a gun.

Aaron Dean mugshot (Credit: Tarrant County Jail)

Attorneys for Aaron Dean formally filed a change of venue request earlier this month. They are claiming their client will not be able to get a fair trial in Tarrant County.

It was in 2019 when Dean and another officer responded to a call about an open door at home during the early morning hours.

Body camera video shows Dean firing his gun through a window, shooting Jefferson as she played video games with her nephew in her mother’s home.

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Following the shooting, Fort Worth police released video showing Dean walk around the side of the house, push through a gate into the fenced-off backyard and fire through the window a split-second after shouting at Jefferson to show her hands.

Atatiana Jefferson

Atatiana Jefferson was 28 years old when she was killed.

Dean, now 37, resigned from the city police force two days after the shooting and was later charged with murder.

Judge Hagerman and state prosecutors appeared frustrated at times Monday with the extensive requests from Dean’s team.

“Any database or any document maintained by any law enforcement agency or prosecutor’s office. That could mean the world. Or do you mean Tarrant county? Or do you mean Fort Worth?” Hagerman asked Dean’s defense attorney Bob Gill. “Can you just give me just a modicum of guidance here?”

Most of the discovery requests were granted though with the judge suggesting the alternate could later provide grounds for appeal.

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The hearing was moved from the Tim Curry Criminal Justice Center down the street to the Tom Vandergriff Civil Court building, and into a larger courtroom. The motions hearing is scheduled to continue Tuesday morning. Staff