Andrew Green, 46, had recently moved to Edmonton from Toronto when he saw a stranded motorist on the Anthony Henday freeway.
He pulled over, and while trying to help, was struck by a passing car.
Scott Pattison, with Edmonton Police Service, says it took several months, but they found a suspect.
He says police were helped by a tip to Crime Stoppers after they put out a call on several occasions for witnesses to step forward.
Kieran Porter, 35, of Edmonton has been charged with hit and run, careless driving and fleeing the scene of a crash resulting in death.
Porter is expected in court on Jan. 16.
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