02/27/2016 12:55 EST | Updated 02/27/2017 05:12 EST

Michael Paul Dockrill Loses Constitutional Challenge Over Mandatory Minimum For Killing Son

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TORONTO, ONTARIO - JANUARY 28, 2016 - Detail of The Canadian Criminal Code with marker written courtrm125. Inside Courtroom 125 at Old City Hall. This is the courtroom where Jian Ghomeshi will be held. (Rene Johnston/Toronto Star via Getty Images)
HALIFAX — A Nova Scotia man who accidentally shot and killed his son when an intruder broke into their home has been sentenced to four years in prison after a judge rejected his constitutional challenge of the mandatory minimum sentence.

Michael Paul Dockrill was convicted in April of criminal negligence causing death for shooting his 20-year-old son Jason.

Brian Church, Dockrill's lawyer, argued in a constitutional challenge that he should not face the mandatory minimum sentence because he's already living "in a prison of grief."

The mandatory minimum sentence of four years for gun crimes was enacted as part of the former Harper government's 2008 criminal justice reforms.

Church told the court that Dockrill's son sold marijuana, and had given his father a rifle a few days before the incident after being threatened.

The court heard there was a break-in at their Halifax-area home on June 12, 2011, and that Dockrill had intended to shoot the intruder, but realized afterward that he had fired at his son.

Church said Dockrill, who he described as a family man, should be given a suspended sentence with probation.

But Crown lawyer Tanya Carter said Dockrill should receive a sentence of five to seven years, because although he did not intend to shoot his son, he did intend to shoot someone — the intruder.

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