RAPID CITY, S.D. (AP) — A man convicted in the 1975 slaying of an American Indian Movement activist will serve life in prison without parole, a judge decided Monday, closing a major chapter in an investigation that has spanned more than three decades. Prosecutors aren't saying if other chapters are to come. John Graham was found guilty last month of felony murder for participating in a kidnapping that ended in Annie Mae Aquash's death. He's the second person convicted in Aquash's death, which garnered international attention and remains synonymous with the 1970s clashes between AIM activists and federal agents. State law from the time of the incident, which prescribes a life sentence for felony murder without mentioning parole, requires a sentence of life without parole, state Attorney General Marty Jackley argued Monday. A South Dakota jury found Graham not guilty of premeditated murder. Judge John Delaney agreed with Jackley but said arguments made by Graham's attorney, John Murphy, had "some merit." "The sentence is preordained at this point," Delaney said, adding that he expected higher courts to make a final decision on what the law means. "The Supreme Court will decide this issue, not I." Authorities believe AIM leaders ordered her death because they thought she was helping the government, which officials have denied. No AIM leader has ever been charged in her slaying, and several people involved with AIM have denied their own involvement. Federal and state prosecutors have confirmed that they continue to discuss the case, and the investigation remains open. On Monday, Jackley refused to say if more charges are forthcoming. Aquash, a member of the Mi'kmaq tribe of Nova Scotia, was active in AIM and close to several of its leaders. By late 1975, however, she started to fear for her life due to circulating rumors that she was an informant, witnesses testified. Graham did not testify at his trial, but spoke Monday before he was sentenced. Graham, wearing a striped jail uniform and chains around his waist and ankles, stood and turned to look at Aquash's daughters as he spoke. He accused witnesses of speaking in "half-truths." a.. 1 b.. 2 c.. Next