The Los Angeles County District Attorney's Office announced the charge on Thursday. Officer Mary O'Callaghan, an 18-year veteran, was charged with felony assault under color of authority.
On July 22, 2012, officers were called to 35-year-old Alesia Thomas' home in the 9100 block of South Broadway Avenue to investigate a case of possible child abandonment. Thomas was placed under arrest following an interview with officers.
O'Callaghan, 48, arrived on scene to help arresting officers with placing Thomas in a patrol car. According to the district attorney's office, Thomas was handcuffed and had leg restraints on at the time.
A police cruiser's camera captured O'Callaghan kicking Thomas in the stomach and groin area and pushing her in the throat. The video has not been released.
Authorities said Thomas lost consciousness in the patrol car. Paramedics were called, and she was transported to an area hospital, where she was pronounced dead.
"The officer's actions that day, as seen on the video, did not meet the expectations I have of our officers in the field. As troubling as this case is, it demonstrates that our system of discovering misconduct is working, and that we will hold our officers accountable for their actions," LAPD Chief Charlie Beck said in a statement Thursday.
Prosecutors have not filed an involuntary manslaughter charge, saying there was insufficient evidence to prove that O'Callaghan's conduct caused Thomas' death.
The Police Commission, which is an independent civilian board with oversight of the LAPD, reported that Thomas had been using cocaine on the day she died. The coroner could not find evidence that either the cocaine or the beating caused her death. The cause of death was categorized as "undetermined" in the coroner's report.
Thomas' mother, Sandra Thomas, says she wants to see the video. She believes more than one officer should be charged.
"All of those officers, they should be punished very harshly. And if there was also a supervisor there, he should be punished as well," she said.
The mother says the single charge does not go far enough.
"It is a terror that has happened, and I have never expected any day would come like this in life for any child of mine," she said.
Prosecutors are expected to ask bail for O'Callaghan be set at $35,000. If convicted, she faces up to three years in state prison.