She says the agency remains "committed to improving our relationships throughout the city". She was released after posting bond.
The bond was re-instated after she was charged with murder, Leach said.
Guyger's indictment comes roughly two months after Texas Rangers arrested her on a warrant to face manslaughter charges.
The indictment is a "step toward justice" for Jean's family, said Sharon Watkins Jones, ACLU of Texas Director of Political Strategies.
Jean's father, Bertrum Jean said of the upgraded charge, "We are not really happy".
When asked by reporters why the jury chose to indict Guyger for murder instead of manslaughter, Johnson said that her prosecutors had presented all the evidence based on more than 300 interviews with witnesses and fully explained the law to the jurors. "And more so, the proper penalty to reflect on the pain she has caused", said Jean's mother. She has since been fired from the department.
According to Guyger, after she shot Jean, she turned on the lights, realized she was in the wrong apartment, gave Jean CPR and called 911. "I said, 'Mom do you want us to stop and go to the grand jury?' And she said 'no, keep going'".
Guyger told authorities she thought Jean's apartment was her own and believed he was a burglar.
Botham Jean's family stood beside Dallas County District Attorney Faith Johnson as she announced the grand jury's decision on Friday afternoon.
Guyger told investigators she had mistakenly entered Jean's unit, thinking it was her apartment, and thought she'd encountered an intruder.
Gugyer was arrested three days after the fatal shooting and immediately posted bail. He was from the Caribbean island nation of St. Lucia.
"In fact, all of the evidence, I think, will show that Amber Guyger made a mistake and when she was in that position that she was justified in the action she took", Rogers said.
Jean's killing thrust Dallas into the national conversation on the intersection of race and law enforcement, a dialogue revived by the high-profile trials of officers charged with murder in police shootings.
Kimberlee Leach, Spokeswoman to Dallas County District Attorney's said by phone that Amber Guyger, 30, yielded to authorities after a grand jury indicted her on a charge of murder in the September 6 death of Botham Jean, 26.
Guyger was arrested on a manslaughter charge on September 9, three days after the shooting, and was booked into the Kaufman County Jail. She then drew her gun and fired, wounding Perez in the abdomen.
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