In a case that could ultimately find itself before the Supreme Court, the association has filed a motion in Quebec Superior Court seeking to strike down sections of Bill C-10.
The targeted sections involve so-called mandatory minimums — penalties that set minimum sentences and leave judges with little latitude if they want to convict someone and proffer a lesser punishment.
The bar association says that not only do mandatory minimums not wind up protecting the public but that they represent an unconstitutional interference from one branch of government, the legislature, in the business of another, the judiciary.
Bill C-10, the Safe Streets and Communities Act, passed earlier this year despite resistance from some provincial governments who called its measures costly, ineffective and a recipe for prison overcrowding.
The omnibus bill sets mandatory minimums for child exploitation and some major drug offences. It stemmed from older bills proposed by the Harper Tories and promised in their 2011 election platform.
The office of Justice Minister Rob Nicholson, responding to the bar association challenge, sent an email Tuesday saying the government firmly believes that mandatory minimums are justified for some infractions.
It says there are 40 cases of mandatory minimums in the Criminal Code and that the recent legislation merely extends an existing practice.
Parts of the Conservative justice agenda have already been struck down in court.
Earlier this year, an Ontario Court ruled that a crack dealer who offered to sell an undercover police officer a gun should not have to face the mandatory minimum sentence of three years for firearms trafficking. The man's lawyer said his client had never had a gun, and never intended to sell one, but was using the gun promise to lure a drug customer.
That Ontario case only dealt with the firearms trafficking provisions from the 2008 Tackling Violent Crime Act, in which offering to sell a gun carries an automatic three-year sentence.
The 2008 bill has suffered several court defeats.
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