Giuseppe Oppedisano, 51, had been charged with dangerous driving causing death after his sport utility vehicle crashed into a motorcycle driven by Mario Laguë more than two years ago.
Justice Paul Lalonde said in his decision Oppedisano had a momentary lapse in judgment when he made a left-hand turn into the path of Laguë's motorcycle.
Oppedisano made a poorly executed turn and there was no evidence he signalled, but Lalonde told an Ottawa courtroom Thursday it was not willful and did not rise to the level of criminal behaviour.
Lague's widow was in court for the verdict but declined to comment.
Laguë, then 52, was on his way to work on Scott Street in Ottawa during the morning of Aug. 12, 2010, when his motorcycle collided with the SUV. He was pronounced dead at the scene.
He had been serving as Ignatieff's director of communications for just under a year.
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