NAVAL STATION GUANTANAMO BAY, Cuba, Jan. 12, 2006 – Preliminary hearings in the case of a Canadian teen accused of murdering a U.S. Army medic in a 2002 Afghan firefight began here yesterday.

Omar Ahmed Khadr, 19, was 15 when prosecutors say he threw the grenade that killed U.S. Army Sgt. 1st Class Christopher Speer. The attack also cost former Army Sgt. Lane Morris an eye.

Khadr appeared in court dressed like a typical teen, wearing an athletic jersey-styled red and blue T-shirt sporting the logo of a Canadian company. The only photo of Khadr that has been made public, taken when he was 15, shows a lanky adolescent. The young man who appeared in court yesterday was bearded and broad-shouldered.

Before the hearing adjourned for the day, presiding officer Marine Col. Robert S. Chester objected to Khadr's attire and instructed attorneys to ensure he did not return to court the following day in a T-shirt. Published rules for courtroom observers expressly forbid such attire.

Khadr fidgeted through the several-hour-long hearing, frequently leaning over to confer with his civilian attorney, American University law professor Muneer Ahmad...