GUANTANAMO BAY, Cuba - A theatre-arts grad with movie and TV experience sat quietly in the courtroom Tuesday, closely scrutinizing the military officers who will decide the war-crimes case against Omar Khadr.

Hired by the defence and paid for by the government, Joe Guastaferro is a trial consultant specializing in jury selection and "courtroom persuasion," according to his website.

"Joe has consulted on and picked juries in numerous high profile criminal cases and has been on the plaintiff's side of several multimillion-dollar verdicts," the website states.

"He has worked with defence teams in 15 capital cases."

Dennis Edney, Khadr's Canadian lawyer, said Guastaferro's role was to advise on jury selection and he would leave as soon as that was done.

"That's what he does," Edney said.

Selection of the Khadr jury — or panel as it is called in military commission parlance — continues Wednesday.

"Omar, say hello," Khadr's Pentagon-appointed lawyer Lt. Col. Jon Jackson said Tuesday after introducing his client to the jurors as a 23-year-old Canadian citizen.

Dressed in a tight-fitting grey jacket, pink tie and black pants in contrast to his usual white prison garb, Khadr stood up.

"How are you?" he said.

Khadr's change of attire was striking, apparently at Edney's behest, who said he raided a closet full of clothes on the island and grabbed some for the accused to wear.

Khadr himself seemed delighted with the effect.

"He glowed — he was allowed to feel human," Edney said.

"When we walked into the courtroom, everyone gasped."

The 11 men and four women comprising the jury pool were drawn from across the U.S. armed forces.

Their identities are shielded under court order, leaving them identified by number.

The most serious of five charges Khadr is facing is murder in violation of the law of war — for allegedly killing an American soldier in Afghanistan in July 2002, when he was 15 years old.

Jurors were asked whether they believed it fair to try 15-year-olds as adults.

All said they did, depending on the nature of the alleged crimes.

"It's done in the civilian sector as well," juror No. 2 said.

"I would imagine that along the way, there have been some sorts of checks and balances."

The panel will also decide on an appropriate sentence if Khadr is found guilty.

Presiding judge Col. Patrick Parrish told the panel they could take Khadr's age into account in deciding his fate.

Parrish also gave the standard cautions to keep an open mind, not infer guilt from the charges, and that certainty "beyond reasonable doubt" was needed for a conviction.

Parrish also said jurors could ask questions of witnesses through him, but said he would decide if the questions were legally appropriate.

In response to questions from prosecutor Jeff Groharing, juror No. 5 said he was aware of the controversy surrounding Guantanamo Bay, which U.S. President Obama pledged to close 19 months ago.

"It's very problematic for the country internationally," said No. 5, an air force pilot.

Khadr fired his civilian lawyers last month, denouncing the legal process as a "sham," and threatened a boycott or to represent himself.

However, he relented, allowing Jackson to stay on the case.

"It is my honour and privilege to represent Mr. Omar Khadr," Jackson told the jury.

The defence can ask once for a juror to be removed for any reason, but can make repeated challenges for cause.

Ultimately, as few as five jurors could be seated to judge the case.

Parrish said the trial was expected to last several weeks.