Bangor — A man convicted in a nearly 40-year-old slaying that many thought would never be solved is facing 45 years in prison, a judge said on Friday.The judge found 57-year-old Philip Scott Fournier guilty in February of killing 16-year-old Joyce McLain. Joyce disappeared while she was out jogging in 1980, and her body was found two days later.Superior Court Justice Ann Murray called it a "cruel and violent act" on Friday and sentenced Fournier to 45 years in prison.Fournier, who was 19 at the time, maintained his innocence Friday. His attorney said he was disappointed with the sentence and plans to appeal.Fournier's attorneys argued that Fournier's memories, which played key roles in the prosecution's case, were not reliable. One defense lawyer has said doubts will linger in the case even after the conviction and sentencing.The case baffled investigators for years. There isn't physical evidence — including no DNA or fingerprints — tying Fournier to the crime scene, but prosecutors say he confessed numerous times over the years. Fournier's attorneys say his memories are unreliable.Joyce's family has been waiting years for justice.Her mother, Pamela McLain, told the judge in a letter that her daughter has been dead for 38 years while Fournier has been free.The teenager, who was from East Millinocket, disappeared after a full day of baby-sitting and piano lessons. She was wearing only sneakers and socks when her body was found. She'd been bludgeoned.The judge found the motive was sexual assault although evidence showed she was not raped, The Bangor Daily News reported. Fournier told the judge that what happened to Joyce was a "horrible thing".