It's the first time the Supreme Court has ruled on the government's controversial tough-on-crime bill, but the case likely won't be precedent-setting.
The high court was confined to a narrow issue surrounding how the law should be retroactively applied to offences committed before it came into force.
In a rare ruling from the bench today, the court dismissed the appeal of a petty criminal from Toronto who argued that he deserved greater credit for pre-trial custody.
Calvin Clarke unsuccessfully argued that even though he was formally charged after the act came into force, he deserved credit because he actually committed the offences prior to that.
The Supreme Court issued a short, verbal ruling from the bench — a rare occurrence — and said reasons would follow in the coming days.
On Feb. 20, 2010, two days before the act came into force, Clarke and an accomplice broke into a Toronto apartment because they wanted to steal a flat-screen TV.
They came across 40 to 50 prohibited firearms, so they stole those too.
Two days later, police arrested the accomplice, and he confessed and implicated Clarke.
Clarke was arrested and formally charged three weeks after the act had been on the books.
At his sentencing hearing in January 2011, Clarke argued that he deserved leniency on his sentence, and should be given double the credit for pretrial custody.
The Tories' act did away with the old practice of giving two-for-one, pre-trial detention credit.
The Ontario Attorney General successfully argued that if the high court accepted that argument it would "manufacture ambiguity where there is none."
Police managed to recover only 11 of the 40 to 50 stolen firearms.
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