And that could spell trouble, justice experts say, as more challenges to the Harper government's "tough on crime" legislative agenda wend their way through the courts.
Thursday's unanimous 8-0 judgment was the third successive court to find that the Abolition of Early Parole Act was in clear breach of the Charter because it imposed new punishment on people who had already been tried and sentenced.
The retroactive changes lengthened the amount of time a non-violent, first-time offender had to spend behind bars before being eligible for parole.
The court found no problem with the law going forward. But it ruled out applying the change to people already behind bars at the time of the bill's passage in March 2011.
"A change that so clearly thwarts the expectations of liberty of an offender who has already been sentenced qualifies as one of the clearest of cases of a retrospective change that constitutes double jeopardy," wrote Justice Richard Wagner, appointed to the bench by Prime Minister Stephen Harper in 2012.
The law was passed at a time when politicians were upset over the sentencing of white-collar criminals, such as fraudster Earl Jones, who, due to the non-violent nature of their crimes, could be paroled after serving only six months or one sixth of their sentence.
Coincidentally, Jones was released Thursday after serving a third of his 11-year sentence for bilking investors out of some $50 million.
And it's those kinds of sentences that help drive the populist appeal of the Conservative justice agenda.
The country's top court has another perspective.
"Regarding the Crown's argument that retrospective application is necessary to maintain confidence in the justice system, I would point out that enactment of Charter-infringing legislation does great damage to that confidence," Wagner wrote in the judgment.
The ruling is just one of a number of pending constitutional challenges currently underway, with lower courts having struck down mandatory minimum sentences in gun and drug cases.
And it comes after a Justice Department lawyer, Edgar Schmidt, blew the whistle on what he says is lax vetting of new federal laws for their ability to withstand Charter challenges. He was sacked by the government and pre-trial motions are to be heard in his case April 4.
"The Department of Justice Act requires the attorney general to report if any government bill is inconsistent with the Charter. That's never been done," Kent Roach, a professor of constitutional law at the University of Toronto, said in an interview Thursday.
Roach said there was a "double failure" on the parole bill, first internally by the Justice Department and then by the parliamentary committee that examined the bill.
He says it's a systemic problem.
"The result is we are going to have more legislation enacted — perhaps for symbolic and expressive reasons — and the courts are going to find at least some of it unconstitutional," he said.
Francoise Boivin, the NDP justice critic, has another name for Roach's "symbolic" legislation: "photo-op or bumper-sticker law."
"I'm saying it's easy politics. It's catering, it's bumper sticker," she said. "You know it's going to be reversed. They're not that dumb."
A spokeswoman for Justice Minister Peter MacKay maintained otherwise.
"Officials at the Department of Justice thoroughly review all government legislation to ensure it will withstand constitutional scrutiny," Paloma Aguilar said in an email.
"The process they use for Charter analysis on government bills is long-standing, and has not changed since the early 1990s."
But Catherine Latimer of the John Howard Society said the parole legislation, struck down by three courts in a row, shows the flaws in the system.
"It's pretty fundamental that the penalties cannot be increased after they have been imposed as part of sentencing," said Latimer.
"The fact that it hadn't been signalled as a Charter risk through the parliamentary process sends out a flag about how effective that process is."
Liberal MP Irwin Cotler, a former federal justice minister, has a private member's bill in the parliamentary queue that would require more rigorous constitutional vetting of all proposed legislation, with reports on the findings.
"The thoughtful guidance that the Supreme Court provides in these cases should be welcomed by the government and used in crafting constitutionally sound legislation," Cotler, who was travelling Thursday, said in an email.
"Regrettably, all too often — particularly in matters of criminal justice — it appears that the Court's wisdom falls on deaf ears."
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