SAN FRANCISCO - For six years, and for no pay, Dennis Edney has represented Omar Khadr, the next prisoner at Guantanamo Bay to face trial in a military tribunal system that the lawyer calls a sham.

So he's stepping outside the courtroom, speaking out about his client and hoping to win a victory in another venue.

His goal is to sway public opinion and pressure the Canadian government into bringing his Toronto-born client home.

Edney is using a series of speaking engagements to try to stir up sympathy for Khadr and put pressure on Prime Minister Stephen Harper to take another look at the case.

Khadr is the only Western citizen still imprisoned at the Guantanamo Bay Navy base as U.S. military prosecutors prepare to bring him to trial.

He is charged with tossing a hand grenade that killed a U.S. soldier during a 2002 firefight at an al Qaeda compound in Afghanistan.

"I realize the only success we're going to have for Omar Khadr is a political one," Edney said in an interview with The Associated Press after addressing aspiring lawyers at the University of San Francisco this week. "So I've moved from being a lawyer to someone who goes on the lecture circuit - all on my own cost, of course."

Khadr, who was captured at age 15, faces a maximum life sentence at a trial expected to begin later this year.

But his attorneys and other critics say a fair trial will be impossible in the special military tribunal system, which departs from traditional U.S. civilian and military courts by allowing hearsay and evidence obtained through coercion.

Requests for comment from the Office of the Secretary of Defense were not immediately returned.

So far, Harper has refused to press for Khadr's release, saying the tribunal at the U.S. Navy base in southeast Cuba should be allowed to run its course.

In May, a Canadian Federal Court judge found that Khadr's treatment by U.S. authorities in Guantanamo - who deprived him of sleep to soften him up in advance of a 2004 visit by Canadian interrogators - violated international laws against torture.

Following that judgment, the court ordered the release of more than seven hours of video documenting interrogation sessions involving the Canadian officials and Khadr from five years ago - interrogations that the U.S. Supreme Court also later ruled took place in an illegal detention environment.

The video, which shows the then 16-year-old pleading for Canada's help and his mother, garnered international headlines as the first ever glimpse at a Guantanamo interrogation.

Last week, defense lawyers filed documents in a Canadian court showing that the U.S. denied a Canadian Foreign Affairs officer's attempts to make sure Khadr had sunglasses and blankets to protect his shrapnel-damaged eyes and body.

Edney said he initially took on the case because it was a just cause and posed interesting legal challenges. Six years later, it's become an opportunity to "educate the public about their obligation to ensure justice is done," Edney said. "I have never before represented anyone who has been treated so badly and abandoned by those who should know better," he said.

One obstacle to the public relations effort has been Khadr's own family, which has a history of involvement in radical Islamic causes and outspoken criticism of the U.S. and Canada.

One of his brothers, Abdullah Khadr, is wanted in the U.S. for allegedly purchasing weapons for al Qaeda. Another brother has acknowledged that their Egyptian-born father, now deceased, and some of his brothers met with Osama bin Laden and fought for al Qaeda.

This family background suggests that Omar Khadr, who was six years old when taken to Afghanistan, should be treated as a child soldier, said Edney.

"He was his mother's baby, and he got caught up in something beyond his control," said Edney. "He was a victim."

The family is attempting to bolster its reputation with a Web site launched this month, TheKhadrLegacy.com, intended to debunk "rumors suggesting the family has violent tendencies or hates Canada."

Omar Khadr's sister Zaynab says in a statement: "Our brother is being held in Guantanamo Bay based on the lies told by both the American and Canadian governments."

Such outbursts, defense lawyers say, have taken away from their efforts to get Khadr out of Guantanamo.

"A lot of people can't see beyond that family, to look at Omar Khadr," said Edney.

He said Khadr is not asking for forgiveness or even freedom.

"Just give him a court room. He's asking for a fair process," he said.