Police in Fort Payne say a district attorney’s investigator has been charged with drunken driving after a witness saw his car hit a guardrail on Interstate 59.

Al.com reports police arrested Gary Williams during a traffic stop at about 3:30 a.m. Saturday. Fort Payne Police Chief Randy Bynum says Williams is an investigator for the district attorney for the Ninth Judicial Circuit, which covers DeKalb and Cherokee counties.

Bynum says a motorist called police after seeing Williams’ Dodge Charger strike a guardrail before turning north on Highway 35 toward Rainsville. He says police officers saw the car moving erratically before they pulled Williams over.