Fargo, N.D. ? Lawyers for imprisoned American Indian activist Leonard Peltier say the government did not have the right to try him for crimes that occurred on a South Dakota reservation.

Peltier, 60, is serving life in prison for the killing of two FBI agents during a 1975 standoff on the Pine Ridge Indian Reservation. He was convicted in U.S. District Court in Fargo in 1977.

In a motion filed Wednesday in federal court, Peltier’s lawyers claim the sentence is illegal and say he should be released from federal prison in Leavenworth, Kan.

“The federal jurisdiction … under which my client was convicted and sentenced depended on the location of the alleged crime, not against whom the crime was allegedly committed,” attorney Barry Bachrach said after the motion was filed. Because the crimes were committed on the reservation, the federal court had no jurisdiction, he said.

It is one of several appeals in the 30-year-old case. Assistant U.S. Atty. Lynn Crooks said a similar claim was denied by a federal appeals court two years ago.

“This one has a little different twist, but I doubt the analysis is going to be different,” Crooks said Wednesday.

Peltier’s lawyers also claim that a recent court ruling on sentencing guidelines shows that the late U.S. District Judge Paul Benson exceeded his authority in handing down two consecutive life terms.

“Not only did the court not have jurisdiction in the Peltier case, but the trial judge inflicted punishment … that the jury’s verdict alone did not allow,” Bachrach said.

Federal sentencing guidelines are being challenged because they allow judges, not juries, to alter sentences, and the U.S. Supreme Court is considering changes.