TORONTO, MARCH 17 -- A Canadian soldier who served as a U.N. peacekeeper in Somalia was found guilty of manslaughter and torture late Wednesday in the beating death of a Somali teenager a year ago and could serve a life sentence for his crimes.

Pvt. Elvin Kyle Brown, 25, a member of the elite Canadian Airborne Regiment, was the first of six paratroopers to face a military court martial for the incident at the Canadian compound in Beledweyne, Somalia. The court martial was conducted at Canadian Forces Base Petawawa near Ottawa.

Canadian Defense Minister David Collenette, speaking in the House of Commons, predicted "a difficult period over the next few months" as the description of the bloody events at Beledweyne are repeated in the ensuing courts martial.

Graphic courtroom testimony over the last six weeks has told more than a tale of soldiers gone amok. It has dealt a blow to Canada's image as the postwar era's preeminent international peacekeeper, and to Canadians' self-image as a people naturally adept at mediating and stabilizing foreign conflicts.

The killings last year of 16-year-old Shidane Abukar Arone and, in separate incidents, of three other Somalis allegedly by Canadian soldiers also have added gravity to a broader debate here about Canada's foreign policy and military posture. This country's once-axiomatic commitment to peacekeeping missions is under its toughest scrutiny yet.

According to witnesses in the military courtroom, Arone was under detention for alleged thievery March 16, 1993, when he was kicked in the face and chest, pummelled with truncheons and burned on the soles of his feet with a lit cigar.

As he begged his captors for mercy, witnesses said, Arone kept intoning one word: "Canada ... Canada."

At least a dozen other soldiers witnessed some or all of the beating, according to testimony, and two posed for "trophy" photographs with the prisoner. Arone's screams were audible over the roar of an electrical generator, the military judges were told, but Canadian military personnel within earshot, officers among them, did nothing to intervene. Arone died of head wounds. Canada reportedly compensated his family with 100 camels, worth about $11,000.

Brown admitted kicking and beating Arone because he "despised thieves." But he testified that the cigar torture and the worst of the kicking and beating were done by another soldier, who cannot be named in Canada under a partial publication ban imposed by the military judges. He is Master Cpl. Clayton Matchee, who is unlikely to stand trial because of brain damage suffered in an unsuccessful suicide attempt after his arrest.

Asked why he had failed to intervene in Matchee's drunken assault on Arone, Brown testified: "I still ask myself that question. I wonder about myself." His lawyer called it a "bad judgment call." Brown had no comment after the verdict was announced late Wednesday night.

Brown and other paratroopers defended their behavior, testifying that they had been encouraged by their superiors to abuse captured Somali thieves as a warning to others preying on U.N. famine-relief installations around Beledweyne.

The 2 Commando unit has been described as a "rogue company" of the Canadian Airborne, a fabled regiment known for its valor and toughness. The Canadian Broadcasting Corp. disclosed last year that some of its members in Somalia were avowed white supremacists.

It has been an article of faith in Canada's military establishment that a well-rounded soldier makes the best peacekeeper and that specialized training for peacekeeping missions was unnecessary. That prescription has worked well over the years when there was a semblance of peace to keep, as in Cyprus, Kashmir, Cambodia and the Dominican Republic.

But now that peacekeepers have been pressed into service as "peacemakers" in war zones, particularly in Croatia and Bosnia where nearly 2,000 Canadians serve, the old verities have become tattered. An internal Canadian Defense Department memorandum quoted in the Globe and Mail newspaper recently said: "The present system is not flexible enough to adapt quickly to changing requirements, particularly those driven by evolving mission complexity."

On the eve of a broad defense and foreign policy review by the Canadian government, a blue-ribbon private sector panel today recommended that Canada abandon the bulk of its Cold War military capabilities, including combat readiness as a NATO member, and concentrate instead on improving training and upgrading equipment for peacekeeping.