The Independent Police Investigative Directorate (Ipid) says a police constable is expected to appear in the Bloemfontein magistrate's court on Monday on a rape charge.
He was arrested by Ipid after a 21-year-old man who had been arrested by the officer laid a charge.
The officer and a female colleague were patrolling at 3.15am on Sunday when they allegedly saw a man urinating in a street. They stopped and the officer told him they would fine him for urinating in public.
When they arrived at the police station, the female officer stayed in the vehicle while the constable went in with the young man.
The constable later came back with the complainant and they dropped him at a taxi rank.
He later lodged a complaint.
TimesLIVE
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