TORONTO/OTTAWA (Reuters) - A landmark decision to overturn a ban on physician-assisted suicide by Canada's top court shows it could take a tough stance on federal government legislation, including security and citizenship bills, that challenge the boundaries of the country's rights-based constitution.
Academics and lawyers said that even though right-leaning Prime Minister Stephen Harper has appointed 7 of its 9 justices since he became prime minister in 2006, the Supreme Court is proving to be a stern defender of the Canadian Charter of Rights and Freedoms that took force in 1982.
"The perception that the current government is pushing rights-diminishing legislation through without apparent regard to the Charter may well be effectively forcing the Court to be more liberal, more activist, and more protectionist," said Jamie Cameron, a professor at the Osgoode Hall Law School in Toronto.
The Supreme Court last week voted 9-0 to overturn a ban on physician-assisted suicide - a position not supported by Harper's Conservative government. Parliament has a year to implement a regulatory framework. Or it can do nothing and allow the court ruling to come into effect in 12 months' time.
It was the latest in a series of defeats for the government. Last year, the court blocked Harper's plans to introduce elections to the Senate and term limits for senators. In 2013, it struck down Canada's restrictions on adult prostitution over the government's objections. Both decisions were unanimous.
While Harper has appointed judges who have a record of being more restrained and less activist, how an individual judge will be affected by the evidence and arguments in a case is unpredictable, noted Carissima Mathen, an associate professor of law at the University of Ottawa.
"It is a cautionary tale for any prime minister who thinks that they can insert certain factors to shift the way the court works," she said.
"The charter provides a framework for argument, it provides a benchmark and now, 30 years on, it provides a whole body of case law such that if the court wanted to go in a radically different direction, it would have to explain itself," Mathen said.
Ironically, the charter was brought into being by former Liberal Prime Minister Pierre Trudeau, whose son Justin is set to face Harper in an election likely to be held in October.
Pierre Trudeau fought to include the charter when he repatriated the Canadian constitution from Britain in 1982. The addition brought Canada more in line with the United States, where the Bill of Rights also offers constitutional protections to citizens.
Harper's party, which includes social conservatives who deride what they say is the court's "judicial activism", has pursued a tough-on-crime agenda.
Appointments to Canada's Supreme Court have been less politicized than in the United States, where potential judges have every aspect of their record, character and life scrutinized, said Philip Slayton, a retired lawyer and author of a book on Canada's top court.
"We know nothing about these people (in Canada). I call them mystery judges because they're appointed, therefore we shouldn't be surprised when they do things that we wouldn't expect," Slayton said.
While no near-term Supreme Court rulings are expected on watershed issues such as abortion or gay marriage - both legal in Canada - some recent legislation pushed through by Harper is expected to be challenged in the courts.
Last year, the Canadian Association of Refugee Lawyers said it is challenging changes to the Citizenship Act, which would allow the federal government to strip citizenship from a dual citizen convicted either in Canada or abroad of criminal offences such as treason and espionage.
Earlier this year, the Canadian Civil Liberties Association said new anti-terrorism legislation may threaten free speech by criminalizing anyone 'advocating' terrorism. The CCLA said the wording is overly broad and may be triggered even when the speaker has no intention of supporting an act of terrorism.
Toronto lawyer Rocco Galati said he sees both these new laws eventually being challenged at the Supreme Court.
"There are a lot of non-violent acts that are caught by the definition of terrorism," he said.
Galati made headlines and history when he challenged Harper's appointment of Justice Marc Nadon to the Supreme Court, arguing he did not meet the specific criteria for judges appointed from the province of Quebec.
Supreme Court appointees from Quebec must be either judges of Quebec's provincial courts or lawyers with at least 10 years standing with the Quebec Bar Association. Nadon was a federal court judge.
The case went all the way up to the top court itself, which quashed the appointment early last year, handing Harper another stinging defeat.
Additional reporting by Mike De Souza in Ottawa; Editing by Jeffrey Hodgson and Grant McCool