FAIRBANKS — One of the four men convicted in the 1997 killing of a 15-year-old boy will be released in 2015 instead of 2020 after a parole board ruled in his favor last week.

An Alaska Department of Corrections parole board agreed last week to move Marvin Roberts to a halfway house in June 2015, department spokesman Richard Schmitz said. Roberts could be released three months later if he takes classes and has been on good behavior while at the halfway house, he said. The halfway house where Roberts would be sent will be determined closer to the release date.

Roberts and co-defendants Eugene Vent, Kevin Pease and George Frese are serving sentences of 33 to 79 years at Hudson Correctional Center in Colorado, though they are in the custody of the state of Alaska. They were convicted in three separate trials of beating John Hartman to death on a downtown Fairbanks street corner on Oct. 11, 1997.

The four men have maintained their innocence while in prison and have fought to win their release through court appeals and parole hearings, a campaign that has been joined by statewide nonprofit the Alaska Innocence Project and the Tanana Chiefs Conference tribal consortium.

It’s unusual for a parole board to give an early release to a defendant who has not confessed to a crime and expressed remorse, said Bill Oberly, the executive director of the Alaska Innocence Project. In the letter to the parole board on behalf of Roberts, Oberly said his investigation into the murder has convinced him that Roberts is innocent. He plans to file a motion with the court when he feels he can prove Roberts is innocent, he said. He also said Roberts has been a good prisoner without any serious rule violations in the past 15 years and has the support of his parole officer.

Among the other three men, Vent had a decision break in his favor recently. An Alaska Court of appeals decision last year gives Vent a hearing that could give him a new trial if he is able to convince a judge that his trial attorney did not provide adequate representation.

Contact staff writer Sam Friedman at 459-7545. Follow him on Twitter: @FDNMcirme.