The Supreme Court will decide whether a former Detroit police officer convicted of killing his girlfriend should get a retrial.

The justices on Friday agreed to hear an appeal from Michigan officials who want to stop a new trial for Burt Lancaster, who was convicted of shooting and killing Toni King in a restaurant parking lot in 1993 with a gun stolen from his mother.

The 6th U.S. Circuit Court of Appeals ordered a retrial so that Lancaster could raise a diminished mental-capacity defense, something Michigan courts would not let him do.

Michigan officials say that decision should be overturned because the diminished mental-capacity defense was not available in Michigan, and federal courts should not second-guess reasonable state court decisions.

The justices will hear the case later this year.