Greg Williams, an assistant district attorney in the 15th Judicial District Attorney's office, faces one count of conspiracy.
Prosecutors have also charged Denease Curry with one count of misprision of a felony for allegedly not reporting the bribery scheme when she had knowledge of it, though it was unclear Thursday for whom she worked.
District Attorney Mike Harson's longtime secretary and office administrator, Barna D. Haynes, pleaded guilty Monday to accepting at least $55,000 in bribes to help criminal defendants get favorable treatment, mainly in DWI cases.
Prosecutors wrote in court filings that the bribery scheme went on for about four years without Harson's knowledge, in part because of a "lack of oversight and safeguards."
All of the deals arranged by Haynes were approved by a judge in special court sessions handled by the same assistant district attorney in Harson's office, federal prosecutors have said.
The person who allegedly paid the bribes has been identified by federal prosecutors only as "co-conspirator No. 1." U.S. Attorney Stephanie Finley declined to say earlier this week whether that person is cooperating in the case or whether he or she would be charged.