A war crimes trial is underway in Canada for the first time in 15 years on Monday when a former Rwandan militia commander faces charges of genocide.

Desiré Munyaneza is facing charges of genocide, crimes against humanity, and war crimes related to the atrocities committed against millions of Rwandans in 1994.

The former militia commander is accused of committing murder, psychological terror, physical attacks, and sexual violence against Tutsis.

He fled Rwanda in 1997 for Canada, carrying a fake Cameroon passport.

He immediately claimed refugee status, saying he would be killed if sent back to Rwanda because he was a Hutu.

His claim was rejected three years later, largely on the testimony of an RCMP war crimes investigator who accused Munyaneza of being linked to the Rwandan massacre.

Munyaneza was living in Toronto when he was arrested by the RCMP in October 2005.

He was taken to Montreal, where he was arraigned day on seven counts of charges, all of which carry a life sentence.

His initial refugee claim was dismissed in Sept. 2000 and twice again on appeal.

He stayed in Canada as he wasn't given notice of his pending deportation. If convicted, he is expected to serve his sentence here.

Observers have said the case, which is being held in Montreal, is unprecedented as Munyaneza is the first person to be criminally charged under Canada's seven-year-old Crimes Against Humanity and War Crimes Act.

A delegation of 17 people, including prosecutors, defence lawyers, and a judge, travelled to Rwanda in January for five weeks of hearings. They interviewed 14 witnesses who are unable to make it to Montreal for the trial.

Among the 20 witnesses expected to testify in Montreal, is Sen. Romeo Dallaire, who led the ill-fated United Nations mission during the Rwandan genocide.

"In this particular case, our understanding is that if the trial is not held here, it is unlikely to be held at all, or if it were to be held in Rwanda then it would simply displace the possibility of trying somebody else," Canadian Centre for International Justice co-ordinator Jayne Stoyles told CTV's Canada AM.

Government of Canada figures show some 800 war criminals and human rights abusers currently live in Canada, the CCIJ said in a statement.

But the CCIJ accuses Ottawa of holding no trials for war crimes since a handful of cases against former Nazis failed in the early 1990s.

"The Canadian government simply washes its hands of the problem, deporting people with no regard to the need for justice," Amir Attaran, a law professor and CCIJ member, said in a statement.

Pacifique Manirakiza, also a law professor and member of the CCIJ, underscored the importance of holding war crimes trials.

"National-level trials like this one are critical to the whole system of international justice," he said. "International courts and tribunals exist, but they are premised on the willingness of domestic courts to do their share."

Stoyles hopes this trial opens the door to future war crimes prosecutions.

"Canada's record on this has been very poor. We have committed do doing this," she said.

"In particular in 2000, when we ratified the treaty to establish an international criminal court, as part of that we committed that we would do these trials here in Canada, as countries around the world are going to do."

Quebec Superior Court Justice Andre Denis will preside over the trial, which comes after several weeks of preliminary hearings in Rwanda.