The Supreme Court of Canada has ruled that Air Canada is not obligated to offer compensation to an Ottawa couple whose  rights were violated when the airline was not able to serve them in French.

In a 5-2 ruling, the court said "there is no dispute that the airline breached its obligations to supply services in French under... the Official Languages Act." But it said it agreed with an earlier Federal Court of Appeal ruling that found the airline did not need to offer the couple damages because the incidents occurred on international flights.

The case involved a couple from Ottawa, Michel and Lynda Thibodeau, who made three trips between Ottawa and the U.S., aboard Air Canada Jazz in 2009.

They stated they could not get service in French when they checked in at the airport, nor at the boarding gate nor aboard the flights. They also complained that an announcement about a change of baggage carousel was made only in English.

While the Thibodeaus are both fluently bilingual, their language of choice was French and they argued they were entitled to be served in French under the Official Languages Act.

At the time, Jazz was an arm of Air Canada which, as a former Crown corporation, has an obligation to offer services in both official languages. (Jazz is no longer part of Air Canada.)

The couple decided to sue in Federal Court. A judge there agreed the couple's rights had been violated and awarded them $12,000 in damages, both to emphasize the importance of their language rights and as a deterrent to the airline. The judge rejected their request for $500,000 in punitive damages.

On appeal, the Federal Court of Appeal reduced the damages awarded to the couple and excluded the incidents that had occurred outside Canada. The court instead called for the airline to offer a letter of apology to the Thibodeaus.

In May 2013, the Commissioner of Official Languages decided to take the case to the Supreme Court on behalf of the Thibodeaus.

In Tuesday's decision, the court noted that Canada has signed an international treaty dubbed the “Montreal Convention.” That convention restricts the types of claims for damages that can be made against international air carriers. Under the convention, compensation can only be sought from international carriers in the case of death or injury, damage or loss of baggage and for delays.

Supreme Court Justice Thomas Cromwell, writing for the majority, said that in this case, the aims of the Montreal Convention take precedence over the Official Languages Act.

"The Montreal Convention’s uniform and exclusive scheme of damages liability for international air carriers does not permit an award of damages for breach of language rights during international carriage by air," Cromwell wrote.

"To hold otherwise would do violence to the text and purpose of the Montreal Convention, depart from Canada’s international obligations under it and put Canada off-side a strong international consensus concerning its scope and effect."

Two judges disagreed, saying by signing the Montreal Convention, Canada did not mean to "extinguish" the rights protected under the Official Languages Act.

"Given the significance of the rights protected by the Official Languages Act and their constitutional and historic antecedents, the Montreal Convention ought to be interpreted in a way that respects Canada’s express commitment to these fundamental rights, rather than as reflecting an intention to subvert them," wrote Justice Rosalie Abella.

The Thibodeaus have made headline several times during fights for their language rights. In 2000, they launched a lawsuit after Michel Thibodeau was unable to order a 7-Up in French on Air Ontario flight from Montreal to Ottawa from a flight attendant who could only speak English.