Toronto-born Omar Khadr has pleaded guilty to all five charges against him, including murder and supporting terrorism, as part of a plea deal with prosecutors at the U.S. military commission at Guantanamo Bay, Cuba.

Khadr is the last Western prisoner at the Guantanamo Bay detention centre. He has been held at the American naval base since October 2002, accused of killing a U.S. soldier in Afghanistan.

The Pentagon said that after a July 2002 attack by U.S. forces on a suspected al-Qaeda compound, Khadr threw a grenade that killed one soldier, Sgt. Christopher Speer, and wounded another.

Khadr was 15 at the time. His defence team argued that their client was a child soldier and should be treated as a victim.

After several years of procedural wrangling and court challenges, Khadr went before a U.S. military court in August. He pleaded not guilty to charges of murder, attempted murder, conspiring with terrorists, spying and providing material support to terrorists and spying.

But the trial was postponed after Khadr's military lawyer collapsed in court during the first week of proceedings.

When the trial resumed on Oct. 25, Khadr withdrew his previous pleas. He was placed under oath so that the military judge, Col. Patrick Parrish, could question him. Asked if he killed Speer in 2002, Khadr answered "yes."

A sentencing hearing for Khadr began the next day.

Khadr was sentenced to 40 years in prison, but the decision by a U.S. military panel was largely symbolic. A pretrial plea deal capped Khadr's sentence at eight years, with the first year to be served at Guantanamo.

On Nov. 1, the Canadian government announced that it would "implement" the plea deal between the U.S. government and Khadr, allowing him to return to Canada after serving a year in Guantanamo.

Just months before he was due to return to Canada, Khadr fired his two longtime lawyers.

Edmonton-based attorneys Dennis Edney and Nate Whitling represented Khadr for years. But on Aug. 4, 2011, he replaced them with two Toronto-based lawyers, John Norris and Brydie Bethell.

The Khadr family

The complexity of the Khadr case has been heightened by Omar's upbringing.

His father, Ahmed Said Khadr, was identified by U.S. and Canadian intelligence sources as an associate of Osama bin Laden and a reputed financier of al-Qaeda operations. He was killed in October 2003 by Pakistani forces — a firefight that left a brother, Abdul Karim, paralyzed.

One of Omar's older brothers, Abdullah Khadr, was ordered jailed without bail in Toronto jail Dec. 23, 2005, as American authorities sought his extradition for alleged terrorism-related crimes. An Ontario Superior Court judge ordered his release after granting a stay of proceedings on Aug. 4, 2010.

Another brother, Abdurahman, was arrested on suspicion of ties to al-Qaeda and spent time at Guantanamo Bay in 2003 before being returned to Canada.

Several members of Omar's family have lived in southern Ontario since emigrating from Egypt in 1977. The family's movements in the 1980s and 1990s — and after the attacks on the United States on Sept. 11, 2001 — have attracted the attention of intelligence officials.

The Khadrs moved to Peshawar, Pakistan, in 1988, when Omar was two. Four years later, Ahmed was nearly killed when he stepped on a land mine in Afghanistan.

The Khadrs briefly came back to Canada so Ahmed could heal before returning to Pakistan and later Afghanistan, where they reportedly lived in a large compound with Osama bin Laden.

The U.S. government says this was about the time Omar attended a military camp that provided instruction on handguns, assault rifles, bomb-making and combat tactics.

Health problems

After his capture in Afghanistan in July 2002, Omar Khadr was airlifted to Bagram Airfield for medical treatment.

Documents from the Foreign Affairs department detail Khadr's many health problems, which result from the battle that led to his capture.

He has no vision in his left eye and his right eye is deteriorating because of shrapnel embedded in the eye's membrane. Khadr is described as "hyper-sensitive" to light and has requested sunglasses, which have not been provided.

He also has shrapnel in his right shoulder, which is painful when the temperature drops, and suffers from nightmares.

Canadian court battle

Canadian Security Intelligence Service officers questioned Khadr at Guantanamo Bay in 2003 and shared the results of their interrogations with the Americans.

A report from the security intelligence review committee, released in July 2009, said documents show Khadr's U.S. captors threatened him with rape, kept him alone and would not let him sleep.

In January 2010, the Supreme Court of Canada ruled that Khadr's rights to life, liberty and security of the person were violated during his interrogation in 2003.

However, the court did not order Khadr's repatriation.

However, the report did not find that CSIS was complicit in any alleged torture.

The government of Canada has refused calls from humanitarian groups and Khadr's lawyers to have Khadr returned to Canada to face justice here.

Given claims of their client's treatment in Guantanamo, Khadr's lawyers asked for a judicial review of the government's stance on repatriation. They argued that returning him to Canada would stop what they said was the violation of his human rights.

The Federal Court of Canada agreed and ordered the government to request his return in April 2009. A panel of the Court of Appeal later upheld that ruling in 2-1 decision.

But the Supreme Court, acting on a government appeal, overturned the lower court rulings in a January 2010 decision.

Years-long road to trial

Khadr was to have been arraigned at a June 2007 hearing. But in a surprise move, the military judge overseeing the special tribunal threw out the charges on a technicality. The Court of Military Commission Review overturned the judge's ruling a few months later and reinstated the charges.

Subsequent hearings focused on Khadr's status, whether he was an "unlawful enemy combatant" on the battlefield — that is, not a member of a uniformed state armed group — a critical legal designation.

Prosecutors did not have a witness who saw Khadr throw the grenade, but the Pentagon said he was the only al-Qaeda fighter left alive and the only person who could have thrown the grenade.

However, a U.S. soldier who took part in the battle said in sworn testimony that two al-Qaeda fighters were alive after the fatal grenade attack.

The future after Guantanamo?

The saga took another twist after U.S. President Barack Obama assumed office in January 2009. The new president promised to close the controversial Guantanamo Bay centre within one year and issued orders to prosecutors that legal proceedings against Khadr and 244 others at the base in Cuba be put on hold, pending a review.

Three months later, the judge presiding over Khadr's military commission proceedings issued an order that the hearings were to go ahead.

The White House announced in December 2009 that up to 100 Guantanamo detainees — including Omar Khadr — would be transferred to a state prison in Illinois. No date for the transfer has yet been provided.

With files from The Canadian Press and The Associated Press