Thousands of Canadians may soon find themselves facing a lawsuit from the makers of the Oscar-winning movie The Hurt Locker, thanks to a federal judge's decision that could throw open the doors to U.S.-style mass lawsuits against copyright-infringing file-sharers.

The lawsuit appears to go against claims made by some in Canada's movie industry that they would not go after individual file-sharers in their efforts to stop unauthorized file-sharing. And it comes at a time when many of those U.S. lawsuits appear to be failing in U.S. courtrooms.

In a decision last month, a federal court judge ordered three internet service providers to hand over identifying information about customers whose IP addresses were logged sharing The Hurt Locker. Bell, Cogeco and Videotron have until this week to hand over the names and addresses to Voltage Pictures, the production company behind Hurt Locker. Lawyers representing The Hurt Locker's makers have been pursuing lawsuits against alleged U.S. downloaders of the movie since the spring of 2010.

The court’s ruling went largely unnoticed until it was reported by University of Ottawa digital law professor Michael Geist, who noted that the lawsuit seems to be going against promises made to Parliament by Canada's film distributors.

Responding to a question about the Hurt Locker lawsuits in the U.S., Ted East, president of the Canadian Association of Film Distributors and Exporters, told Parliament last spring, "We're not interested in sweeping up the John Does. We're looking for legislation that basically stops online piracy and illegal file sharing, which requires changes to the bill that exists."

This is the second major attempt to bring file-sharing lawsuits to Canada. The first, in 2004/2005, was the BMG Canada v. Doe case, in which a number of the world's largest reecording companies attempted to sue music file-sharers, but which resulted in a federal judge declaring that file-sharing was legal in Canada.

That ruling did not stand long. The federal Court of Appeal eventually dismissed the BMG lawsuit, but also set aside the judge’s declaration that file-sharing is legal. Since then, the question of file-sharing’s legality in Canada has remained open-ended.

In the U.S., lawsuits against file-sharers have been far more prolific and, so far, more successful. But the practice of suing file-sharers has resulted in some extreme cases, such as a Minnesota mother who was ordered to pay $1.5 million for sharing 24 songs.

And a series of recent developments suggests some judges in the U.S. may be turning against the practice of mass lawsuits. Last week, a Calfornia judge dismissed all but one of 5,000 defendants in a file-sharing case, calling the suit a “massive collection scheme.”

In another case earlier this year, a judge rejected a file-sharing suit, saying the plaintiff couldn't sue an individual because of a computer IP address found to be sharing files illegally, because an IP address is not a person.

Indeed, since the recording and move industries started launching mass lawsuits in the U.S., courtrooms have been flooded with letters by defendants claiming they were wrongly targeted because their name was associated with an IP address, saying they had never illegally downloaded any files. In some cases, defendants weren’t aware that housemates or relatives were file-sharing, and in some cases defendants’ wireless routers were used by neighbours to file-share.

In his report on the Hurt Locker court decision, the University of Ottawa's Michael Geist argues that the lawsuit is a sign that the Conservative government proposed's copyright reform bill is a good idea.

"The prospect of thousands of Canadian peer-to-peer file sharing lawsuits -- with potential liability of tens of thousands dollars per person for a single movie -- highlights why the government was right in Bill C-32 to reform the statutory damages provision to distinguish between commercial and non-commercial infringement," Geist wrote.

The current copyright act allows fines of up to $20,000 for an unauthorized instance of file-sharing. Under the new law, which the government has said it will reintroduce this fall, non-commercial file-sharing fines would be capped at $5,000.

But given the quantities of files shared online, a fine of that size could still expose file-sharers to tens of thousands, if not hundreds of thousands, of dollars in damages.

Canada’s music and movie industries say that copyright-infringing file-sharing is costing their industry, artists and the economy as a whole billions of dollars. The Canadian Association of Film Distributors and Exporters says that file-sharing reduced economic activity by $1.8 billion and reduced employment by 12,600 jobs in 2009-2010.

CORRECTION: This story has been modified from its original version to make clear that the file-sharing case involves a federal court, not a Quebec court.