After completing law school, Benham served in the U.S. Army Reserve, attaining the rank of Captain.
In 1984, Justice Benham was appointed by Governor Joe Frank Harris to the Georgia Court of Appeals, where he served for five years following his statewide election to the court,[2] distinguishing himself as the first African American to win statewide election in Georgia since Reconstruction.
In 1989, Justice Benham was further distinguished as the first African American to serve on the Supreme Court of Georgia, following his appointment by Governor Harris.
Justice Benham holds membership in numerous professional organizations, including eight national, state, and local bar associations, the American Judicature Society, the Lawyers' Club of Atlanta, the National Criminal Justice Association, the Georgia Bar Foundation, the Georgia Legal History Foundation (Trustee), and Scribes - The American Society of Writers on Legal Subjects.
He is the former chairman of the Governor's Commission on Drug Awareness & Prevention, a member of the State Bar Task Force on the Involvement of Women & Minorities in the Profession, the Georgia Commission on Children & Youth, the National Association of Court Management, and a member of the National Conference of Chief Justices, a member of the Federal-State Jurisdiction Committee, President of the Society for Alternative Dispute Resolution, Chairman of the Judicial Council, Chairman of the Chief Justice's Commission on Professionalism, and a member of the Governor's Southern Business Institute.