ALBANY — The New York State attorney general, Eric T. Schneiderman, announced the indictment on Friday of a county district attorney over his handling of a grand jury investigation into the fatal police shooting of an unarmed motorist last year.

Joel Abelove, the district attorney in Rensselaer County, was charged with a single felony count of perjury in the first degree and two counts of official misconduct, a class A misdemeanor.

The charges — a rare instance of a county prosecutor being charged by the state attorney general — stem from the death of a 37-year-old black man, Edson Thevenin, who was shot and killed by the police during a traffic stop in Troy, N.Y. on April 17, 2016.

The case against Mr. Abelove, a Republican, does not focus specifically on the circumstances of Mr. Thevenin’s death, who was shot after an altercation with Troy police after a brief chase involving a traffic stop on suspicion of drunken driving. The chase ended with a Troy police sergeant, Randall French, shooting Mr. Thevenin eight times, killing him, after the officer was pinned between his cruiser and Mr. Thevenin’s vehicle.