Georgia Bureau of Investigation agents arrested Christopher Wayne Harlin, 39, Thursday on one count of sexual assault of a person in custody.
Alma Police Chief Brandon Sellers fired Harlin immediately after his arrest. Harlin was a corporal who had been with the department about 11 years.
"We've got to police ourselves like we police everybody else," Sellers said.
After his booking into jail, Harlin was freed on bail. He could not be reached for comment Friday. If convicted, he faces 10 to 30 years in prison.
Harlin is accused of fondling the woman, 21, early April 17 in a room at the police department, which is in the same building as the Bacon County Sheriff's Office and jail.
The woman had been in jail on charges of driving with a suspended license and violating probation in Lowndes County, Sellers said.
She and Harlin were acquaintances before her arrest. She told investigators that she consented, Sellers said. Under Georgia law, consent is not a defense when the victim is under control of a law enforcement officer.