Over the past several weeks, the Canadian press has reported that at least six detainees currently held at Guantanamo are interested in seeking refugee status north of America’s border. But the Canadian government should be wary of accepting them. Canadian officials should carefully evaluate their cases, including the unclassified files the U.S. government has released for each of them. Three of the six detainees have especially troubling ties to al Qaeda. And there is no question that one of them is an exceptionally dangerous threat.

Consider the case of a Mauritanian named Mohamedou Slahi, who spent only a few months of his pre-Guantanamo life in Canada. During his hearings at Guantanamo, Slahi expressed an interest in returning to Canada. It would be surprising, however, if the Obama administration set him free. There is little doubt that Slahi was an important al Qaeda recruiter, who operated in the West for the better part of a decade.