Ottawa

Omar Khadr pulled the pin from a grenade and tossed it at Sgt. First Class Christopher Speer, a U.S. Army Delta Force medic, on July 27, 2002. Those are the facts to which Mr. Khadr, a Canadian citizen, confessed when he pleaded guilty before a Guantanamo Bay war-crimes commission.

For several years Mr. Khadr had been living and training with al Qaeda in Afghanistan under the tutelage of his father, Ahmed. The Khadrs reportedly lived in Osama bin Laden’s Kandahar-area compound.

Speer died of his wounds 1½ weeks after the attack, which left another soldier, Sgt. First Class Layne Morris, partly blind. Mr. Khadr, badly wounded, was treated and transferred to the Cuba base. In 2012 the U.S. returned him to Canada to serve the remainder of his eight-year sentence.

Mr. Khadr was just shy of his 16th birthday at the time of the attack. In 2010 Canada’s Supreme Court held that the interrogation of Mr. Khadr at Guantanamo Bay by Canadians in 2003-04 violated Canadian standards for the treatment of detained youths. These violations occurred during the mandates of Liberal Prime Ministers Jean Chrétien and Paul Martin. The Supreme Court left it to the government, then headed by Conservative Stephen Harper, to determine an appropriate remedy, and to the civil courts to rule on any damages.