Jury selection in the murder trial of a white former Dallas police officer will begin on the anniversary of the day she fatally shot an unarmed black neighbor in his own apartment.

State District Judge Tammy Kemp and the attorneys decided Thursday to begin interviewing jurors for Amber Guyger's trial on Sept. 6, one year after 26-year-old Botham Jean's death. Testimony begins Sept. 23.

Guyger told investigators that when she entered Jean's apartment, which was directly above hers, she mistook it for her own. She was fired following the incident.

During the 12-minute hearing, Kemp also quizzed the lawyers about the leaking of Guyger's 911 call after the shooting despite a gag order.

"I really was dismayed to find out that someone lacked the integrity and fortitude to honor the gag order," Kemp said.

Prosecutor Jason Hermus and defense attorney Robert Rogers said they didn't leak the audio and that they didn't know who did.

Dallas police are investigating whether any of their officers released the recording, Hermus said. On the call, Guyger can be heard apologizing to Jean, who was a 26-year-old native of the Caribbean island of St. Lucia. Jean was a graduate of Harding University in Searcy, Arkansas who worked in Dallas for an accounting and consulting firm.

"We want this case to be tried in the courtroom. We want this case to be tried in Dallas County, and the frustrating part right now, we feel that strategically, people are leaking this type of information now a couple of months before the trial for the mere purpose of trying to taint the jury pool," said Daryl K. Washington, who is the civil attorney for Jean's family.

A lawsuit that Jean's family filed against the city and Guyger is pending in federal court. It is doubtful the civil case will move forward until the criminal case is decided.