On 12 March 1976 Calgary police officer Allan Keith Harrison was shot and killed following a robbery at the Ingleside Credit Union. By the end of the year, Janise Marie Gamble, a twenty-one year-old woman from Peterborough, Ontario, had been convicted of murder in the first degree and sentenced to the mandatory twenty-five to life. It was clear that Gamble had not fired the shot that killed Henderson, but it was less clear whether she had participated...