VANCOUVER - The arrest of former Bosnian Serb leader Radovan Karadzic and his appearance before a Yugoslav war crimes tribunal in The Hague is a victory for many Canadians who have been deeply involved in the ugly aftermath of the ethnic and religious war following the breakup of the former communist federation.

At the centre of Karadzic's prosecution for crimes against humanity is the July 1995 massacre of about 8,000 Bosnian Muslim men and boys at Srebrenica after the city's capture by Bosnian Serb forces.

Bosnian Serbs also took 55 Canadian peacekeepers hostage to use as human shields against potential NATO bombing in the war's closing stage. The photo of Capt. Patrick Rechner chained to a lightning rod brought home that this was no ordinary peacekeeping mission.

And, Canadians like Rechner, who watched the war unfold, could be potential witnesses at Karadzic's trial, says Walter Dorn, a professor of defence studies at Royal Military College and Canadian Forces College.

"We had a huge number of people who were in a position to see the atrocities that were going on in Bosnia," says Dorn, an expert in the role of intelligence in UN peacekeeping operations.

"There's going to be a lot of focus on Srebrenica but there were a lot of other things that Karadzic should be held accountable for. The Canadians were directly witnessing the ethnic cleansing going on more generally."

Canada's role since the war ended may also play a key part in the trial.

Many Canadians have helped sort through the grisly evidence of genocide at Srebrenica and elsewhere.

"The Canadian involvement in the analysis of the remains is huge," says Dr. Mark Skinner, a forensic anthropologist who worked in Bosnia.

"My role largely throughout much of that time was monitoring the mass-grave exhumations, some related to Srebrenica, of course, and other mass graves," says Skinner, a professor at Simon Fraser University.

At the Lukavac Reassociation Centre near Tuzla, Bosnia, experts under the direction of another Canadian, forensic anthropologist Cheryl Katzmarzyk of Edmonton, are still trying to match up and identify dismembered body parts from the Srebrenica massacre.

To date, the centre has developed DNA identifications for 5,000 men and boys, says Katzmarzyk.

"At this time, we have excavated and examined 23 secondary mass graves related to one execution event," she says. "We are aware that there are several more graves that need to be exhumed."

The centre, run by the International Commission for Missing Persons, was established in 2005 but Katzmarzyk has been working in Bosnia for a decade.

There are at least half a dozen Canadians working for the commission and the centre, where experts are trying to preserve evidence for future war crimes cases. It's a task made more difficult by the fact that remains were often scattered in different sites to frustrate any future investigations.

The main role is to help relatives find out what happened to their loved ones, Katzmarzyk says.

"The reassociations are extremely complex and one person's remains may be recovered from several secondary mass graves dozens of kilometres apart," says Katzmarzyk.

"We don't really need to put them back together. We associate them for identification purposes but we certainly reassociate them as much as possible for the victims themselves and their family members."

Karadzic's arrest caused hardly a ripple in the community, Katzmarzyk says, aside from a few honking horns.

"Perhaps part of it is that it does not change the fact that those men and boys were executed and we are still in the process of trying to recover, identify and repatriate them to their family members," she says.

Hundreds of Canadian police officers also volunteered to help rebuild Bosnia's fractured justice system after the war ended.

RCMP Cpl. Glenn Stoddard spent six months in 1998-99 in the strategic Brcko district, a flashpoint bordering Croatia and Serbia, where his job was to help create a multi-ethnic police force that would deliver even-handed law enforcement.

"It was considered, at the time that I went there, as an undesirable posting," says Stoddard, now a proceeds-of-crime investigator in Edmonton.

The young cops excelled, he says, but whether the forced co-operation and by-the-book policing has survived is hard to say.

"I would like to think that it continued but I don't know if it did," says Stoddard.

Stoddard's roommate, Ottawa police Staff Sgt. Chris Renwick, worked as a human-rights investigator, essentially an ombudsman and referee in disputes between returning refugees and the dominant Serbs who may have appropriated homes and property.

Centuries-deep hatreds meant concessions were bitterly fought.

"Every Serb you talk to will give you a history lesson before they get to the root of their problem at the time," says Renwick.

"You had small little victories but there was a lot of frustration. Just small injustices to be changed were very difficult to implement."