American Indian activist Leonard Peltier, imprisoned since 1977 for the deaths of two FBI agents, has been denied parole after authorities decided that releasing him would diminish the seriousness of his crime, a federal prosecutor said. Peltier, who claims the FBI framed him, will not be eligible for parole again until July 2024, when he will be 79 years old. U.S. Attorney Drew Wrigley announced the decision of the U.S. Parole Commission in mid-August.

Peltier is serving two life sentences for the execution-style deaths of FBI agents Jack Coler and Ronald Williams during a June 26, 1975, standoff on South Dakota’s Pine Ridge Indian Reservation. He was convicted in Fargo, N.D., in 1977. He has said the FBI framed him, which the agency denies, and unsuccessfully appealed his conviction numerous times.

He also was denied parole in 1993. Peltier had a full parole hearing for the first time in 15 years in July at the Lewisburg, Pa., federal prison where he is being held. The hearing was closed to the public, but Seitz said he focused on factors that would support parole.

He said a representative from the Turtle Mountain Band of Chippewa reservation in North Dakota, where Peltier grew up, said the tribe had made arrangements to incorporate Peltier back into society should he be paroled. Seitz also said Peltier has had no documented misconduct in prison in the past 10 years.

Wrigley said Peltier’s past criminal conduct while behind bars was a factor in the Parole Commission’s decision. He claims that in 1979, Peltier escaped for a time in California, and that he also has had numerous infractions in prison.

Seitz said earlier that Peltier is in poor health, with diabetes, high blood pressure, a jaw problem and a urinary system ailment. Parole was abolished for federal convicts in 1987, but Peltier remains eligible because he was convicted before then.