In a letter obtained by The Canadian Press, the Office of the Correctional Investigator urges prison authorities to take into account evidence that Khadr poses minimal threat and should be classified as such.
"(Correctional Service of Canada) officials also note that there is no evidence Mr. Khadr has maintained an association with any terrorist organization," the letter to CSC's senior deputy commissioner states.
"It is well documented by CSC officials that Mr. Khadr is fully engaged in his correctional plan and he has actively developed a strong, pro-social network of support since his incarceration."
The letter this month by Ivan Zinger, executive director of the independent Office of the Correctional Investigator, is the office's third such complaint since Khadr returned to Canada from Guantanamo Bay in September 2012 to serve out the rest of an eight-year sentence for war crimes.
Corrections recently reclassified Khadr, 27, and transferred him from the maximum security Edmonton Institution to the medium security Bowden Institution in Innisfail, Alta.
But the ombudsman argues the change doesn't go far enough, given that Khadr pleaded guilty in October 2010 before a U.S. military commission to war crimes he committed in Afghanistan as a 15 year old.
Canadian prison authorities have called Khadr "polite, quiet and rule-abiding," and someone who "does not espouse the criminal attitudes or code of conduct held by most typical federal offenders."
Most importantly, perhaps, CSC officials note they have no information to indicate he "espouses attitudes that support terrorist activities or any type of radicalized behaviour."
Correctional authorities, citing privacy concerns, have repeatedly refused to discuss Khadr's case.
A spokesman for Public Safety Minister Steven Blaney repeated a comment from last summer in which he noted Khadr had pleaded guilty to "heinous" crimes and that the government would fight any attempt to lessen his punishment.
One of Khadr's Canadian lawyers, Dennis Edney, called it "disgraceful" that authorities have ignored the ombudsman's repeated recommendations.
"This independent body has on several occasions pointed out that a plethora of evidence testifying to the fact that Omar Khadr has no ideological leanings or poses a security threat has been ignored," Edney said in an interview Wednesday.
"This is a government that has no compassion even for the most vulnerable in our society. It is spiteful and wishes to run out the clock on Omar by keeping him in prison for as long as they can."
In a separate letter this month to Blaney and Justice Minister Peter MacKay, Amnesty International expresses concern that "serious human-rights matters remain unresolved" in Khadr's case, among them his security classification.
Amnesty notes Khadr has been incarcerated since July 2002, and that the Supreme Court of Canada has found Ottawa violated his rights.
The organization urges the Conservative government to appoint a "respected" sitting or retired judge to review the entire file and recommend ways to resolve the human-rights and legal issues involved.
Among other things, the letter notes Khadr's status as a 15-year-old "child soldier" when the U.S. accused him of throwing a grenade that killed an American special forces soldier.
"The issues are complex," the letter states. "The human-rights consequences are grave."
In an affidavit in December, Khadr said he only pleaded guilty to war crimes as a way out of Guantanamo Bay, Cuba.
He said he had no memories of the firefight in Afghanistan or of the grenade that killed Sgt. Christopher Speer, and insisted he did not attack any U.S. forces who entered the compound after the battle was over.
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