The Supreme Court of Canada will hear arguments on whether the charter protects the right to strike in a case that could have an impact across the country.

The Saskatchewan Federation of Labour asked the high court to weigh in on provincial legislation that restricts who can strike and on other changes it says make union certification difficult. The federation argues the changes infringe on the freedom of association and freedom of expression.

"It is an important, very, very important case, because it would ensure under the charter that the right to strike is one of those protected rights," federation president Larry Hubich said Thursday.

But Saskatchewan Labour Minister Don Morgan says the right to strike would be a major issue across the country if it were to be upheld by the court.

"That would certainly change the dynamic of virtually everything that you do, because the focus of labour law is the right to withdraw services versus the right to maintain services or things that the public requires," he said.

"That could be a significant game-changer."

The dispute started in December 2007 when the Saskatchewan Party introduced the legislation shortly after winning its first provincial election.

The essential services law states employers and unions must agree on which workers are so needed they can't walk off the job. But unions were outraged because the law also states that if the two sides can't agree, employers can dictate who is essential.

The legislation passed in May 2008 and the court challenges began.

A Regina Court of Queen's Bench judge ruled in February 2012 that the law was unconstitutional.

Justice Dennis Ball said at the time that "no other essential services legislation in Canada comes close to prohibiting the right to strike as broadly, and as significantly." However, Ball upheld the principle of essential services and gave the government 12 months to fix the law.

The government went to the Saskatchewan Court of Appeal and argued that the lower court's decision broke new ground when it stated there is charter protection for the right to strike.

The unions also appealed the Court of Queen's Bench ruling, but on a different front. They wanted the appeal judges to overturn part of the lower court ruling that said the government's Trade Union Amendment Act didn't violate the charter.

The Court of Appeal overturned the lower court and said the right to strike is not protected by the charter. The appeal court also dismissed the trade union act challenge.

The federation said in June that it would seek the Supreme Court's opinion.

Kevin Banks, assistant professor of law at Queen's University, said it's not surprising that the Supreme Court granted leave to hear the case because of the conclusion reached by the Saskatchewan Court of Appeal.

"Basically, the Saskatchewan court says 'yes, the Supreme Court has found that there is a right to bargain collectively. Yes, it's possible to argue that that also means the right to strike is protected," explained Banks.

"But it's not sufficiently clear from the Supreme Court's more recent cases that the right to strike is protected and the Supreme Court has an older line of cases -- which it hasn't expressly overruled -- that said the right to strike was not protected.

"Essentially, the Saskatchewan Court of Appeal is saying there's a lack of clarity in the Supreme Court's jurisprudence on the right to strike and it is really up to the Supreme Court to clarify."

Banks said what the Supreme Court decides is important.

"Other provinces will definitely be watching because the precedent set in this case could affect all Canadian jurisdictions," said Banks, who is also director of the Centre for Law in the Contemporary Workplace.

A hearing date has not yet been set.

Morgan expects arguments could be made before the court in spring 2014. It usually takes several more months before a decision is reached.

"They could say yes, we support what the Saskatchewan Court of Appeal did and then that becomes in effect a national ruling," said Morgan.

"Or they could say no, we're striking it down, or we think this is what changes you should make."

Morgan said the province is already working to change the rule about employers dictating who is essential.

"We need to have a better method of determining how services are provided, who picks the people, whether you decide whether it's (by) job descriptions or individuals, so that's a discussion that's ongoing right now," he said.

Hubich said whatever the Supreme Court decides it will be the law of the land.

"Obviously, we are hopeful that the Supreme Court of Canada will rule that the two pieces of legislation are unconstitutional and if they were to do that, then yeah, that would set a precedent. There are other cases that have established that collective bargaining is a charter right and we expect and hope that the Supreme Court will reaffirm that," said Hubich.