But the Canadian government maintains that letting Khadr out would undermine public confidence in the justice system, subvert international law and damage this country's relationship with the United States.
Nathan Whitling told a bail hearing in Edmonton on Tuesday that his client should get bail while he appeals his war-crimes conviction before a U.S. military court. He said the court has put the appeal on hold and might not make a decision before Khadr completes his sentence.
"We could all be retired by the time the appeal is done," Whitling told Justice June Ross of Court of Queen's Bench.
He said Khadr has a right to seek bail pending an appeal, just as other prisoners do in both Canada and the U.S.
"Mr. Khadr should not be treated differently."
Khadr pleaded guilty in 2010 to five war-crimes charges, including murder, for killing an American soldier in Afghanistan when he was 15.
After spending nearly a decade in Guantanamo Bay, Khadr was sentenced by a U.S. military commission to an additional eight years and shipped to Canada. He then said he only pleaded guilty to get out of Guantanamo.
Bruce Hughson, a lawyer representing the federal government, told court that releasing Khadr might encourage other Canadians convicted in foreign countries to ask for transfers and file appeals so they can also seek bail.
It would affect the willingness of countries to send offenders to Canada, he said.
"It would destroy the transfer system," Hughson told the judge. "This isn't just about Mr. Khadr."
Hughson said the proper route for Khadr's release is through the Parole Board of Canada. Khadr is set to appear before the board in June.
Now 28, Khadr is more than halfway through his sentence. He is a medium-security prisoner at Bowden Institution in central Alberta.
He won an earlier Alberta court decision that said he should be serving his sentence in Canada as a youth. The government is appealing that ruling to the Supreme Court.
If released on bail, Khadr plans to live in Edmonton with one of his other lawyers, and a university has agreed to let him enrol as a student.
Whitling told the court that if Khadr got bail but lost his appeal, he fully understands he would have to go back to prison to complete his sentence.
The lawyer has filed a psychologist's report and several letters of support with the judge, and pointed out about two dozen supporters in the courtroom.
"Everybody says he's not a threat. He's a good kid. He's not radicalized."
The hearing is to continue Wednesday.
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