UPDATE 2-Appeals court upholds Canada-U.S. asylum-seeker agreement

(Adds detail from ruling, reaction)

By Anna Mehler Paperny

TORONTO, April 15 (Reuters) - A Canadian appeals court on Thursday upheld a Canada-U.S. agreement to turn back asylum-seekers, overturning a lower court ruling, siding with the federal government and setting up a possible Supreme Court showdown.

The ruling is a victory for Canada's federal government, which had launched an appeal defending the agreement and, by association, U.S. immigration detention practices, which it said do not "shock the conscience."

At issue was whether the Safe Third Country Agreement, a pact signed in 2002 and under which asylum-seekers trying to cross between Canada and the United States at a formal border crossing are turned around and sent back, violates an asylum-seeker's fundamental rights under the Canadian Charter of Rights and Freedoms.

It was not the agreement itself that may have been causing these alleged infringements on the claimants’ rights, the ruling said, but the periodic reviews of the designation of the United States as a “safe” country as well as “related administrative conduct.”

The challenge should have focused on those reviews, the ruling said, even though the government has kept them secret.

The ruling also said that the experiences of just 10 asylum-seekers cited were not enough to draw conclusions about the U.S. immigration detention system and potential rights violations.

That's a problematic bar to set, said University of Ottawa immigration law professor Jamie Chai Yun Liew, adding that the ruling and the continuation of the agreement fly in the face of the reputation Canada builds for itself as a champion of refugees,

"It erodes our commitment to refugee protection and also erodes our reputation in upholding the rights of refugees," she said.

Last year a federal court ruled that the agreement violated asylum-seekers' right to life, liberty and security of the person. Refugee lawyers argued the agreement also violated asylum-seekers' equality rights at the Federal Court of Appeal this year.

They said the agreement should be struck down because asylum-seekers who were turned back often found themselves locked up indefinitely in immigration detention. They also argued that people trying to make refugee claims that might be accepted in Canada, such as those on the grounds of gender-based discrimination, risk being sent back by the United States to their countries of origin.

Canada's government argued that the pact was a necessary part of managing a shared border and that people in U.S. immigration detention had access to counsel and due process. Should the agreement be dissolved and asylum-seekers allowed to enter through land border crossings and make refugee claims, the government argued, it would suffer "irreparable harm."

The legal battle may not be over, however: Refugee lawyers may apply to be heard by Canada's Supreme Court.

The Canadian government did not immediately respond to a request for comment.

During the administration of then-President Donald Trump, tens of thousands of asylum-seekers crossed into Canada between ports of entry to skirt the Safe Third Country Agreement, which only applies to formal border crossings. (Reporting by Anna Mehler Paperny; Editing by Aurora Ellis and Jonathan Oatis)