PITTSBURGH (AP) -- A city police officer has been convicted of drunken driving and involuntary manslaughter in an off-duty motorcycle crash that killed his fiancee's friend -- but was found not guilty of a more serious charge that carried a mandatory minimum three- to six-year prison term. Allegheny County Judge Jeffrey Manning on Tuesday found Adam Lewis, 31, not guilty of homicide by vehicle while driving drunk, which means the judge didn't believe the officer's intoxication led directly to the fatal crash about 2:30 a.m. on Sept. 26, 2010. Lewis' conviction on the lesser manslaughter count instead means the judge found the officer was reckless and showed gross negligence in the crash that killed 28-year-old Jessica Marie Lojak, of Fawn Township. Prosecutors and defense attorney William Difenderfer agreed that Lewis' blood-alcohol content was 0.11 percent, exceeding the state's 0.08 percent limit for drivers. Lewis was fired in March 2011 and his attorney said the former officer likely faces incarceration when he returns for sentencing Jan. 6 before Manning. Lojak was one of several friends who attended a bachelorette party for Lewis' fiancee on Pittsburgh's nightclub-laden South Side. Lewis, who met up with the group, was allegedly speeding with Lojak on the back of his motorcycle when he lost control on a bend and overcorrected, crashing head-on into a sport utility vehicle. The judge issued the verdict Tuesday, after mulling testimony from last week. "It's much easier for a fact finder to deal with cases of evil," Manning said in rendering the verdict. "That's not what we have here. What we have is the death of a beautiful, vibrant young woman celebrating with her friends a future wedding -- a death completely unintended, as so many traffic accidents are."