Dallas County sheriff’s deputy arrested after complaint alleges mistreatment of man in custody, authorities say

A Dallas County sheriff’s deputy was arrested Thursday after a complaint filed with the sheriff’s office raised concerns about mistreatment of a man in custody during a “prisoner transport,” authorities said.

Austin Palmer, 33, was booked into the Dallas County Jail about 12:45 p.m. on charges of assault causing bodily injury and official oppression, both misdemeanors. He was released after posting $3,000 bond about 3:30 p.m.

Both charges show an offense date of Oct. 7, 2019, in online case records.

The sheriff’s office did not elaborate on the specific allegations in the complaint that led to Palmer’s arrest.

The complaint spurred both an internal affairs investigation and a criminal investigation, the sheriff’s office said.

Sheriff Marian Brown called a news conference Friday morning to provide more details about the case.

“The Dallas County Sheriff’s Office is committed to our core values of integrity, professionalism, and accountability,” Brown said in a written statement.

Palmer had been employed by the Dallas County Sheriff’s Office since November 2007, when he began working as a detention service officer. He was promoted to deputy in 2013, the office said.

He has been placed on administrative leave, the sheriff’s office said.