In a legal brief submitted Monday to the Court of Queen's Bench of Alberta ahead of a March 24-25 hearing, the government argues that granting Khadr's application would undermine public confidence in the justice system.
It also claims that releasing Khadr would subvert an international law principle of respect for another state's right to administer criminal justice.
Ottawa warned that enforcing Khadr's US sentence would undermine Canada's legal and treaty obligations, which could jeopardize future prisoner transfers if the United States no longer believes Canada will hold up its end of these bargains.
The United States has been by far the top source of such transfers in the past decade with 2,101 Canadians permitted to serve the rest of their sentences here, according to government figures.
Khadr was repatriated to Canada in September 2012 after spending 10 years in the US military prison in Guantanamo Bay, Cuba following his arrest in Afghanistan as a teenager.
He was sentenced to eight years in 2010 following a military hearing in which he agreed to plead guilty to murder in violation of the laws of war, attempted murder, conspiracy, providing material support for terrorism and spying.
Ottawa noted that as part of the plea agreement, Khadr waived his right to seek early release.
But Khadr has said he only agreed to the deal in order to get out of Guantanamo.
He is also seeking parole.