Her latest challenge was to investigate the killing of 40 ethnic Albanians in southern Kosovo. But Serb authorities have barred the investigators from entering the province.

Louise Arbour: "We are the living memory of what happened"

In an interview for BBC World's Hardtalk, recorded in the Hague before the massacre in Racak, Louise Arbour gave an insight into her two years as the UN's chief war crimes prosecutor

She spoke calmly about the horrors she has to face in her job, explaining to Hardtalk's Tim Sebastian that she has a "very detached professional manner."

"The danger is if you had the capacity to feel, you wouldn't be able to do the work," she said.

"The part that we play into addressing these issues, I think, has to be approached in a very detached professional manner. If we were driven by the emotional human reaction that others would have when they see that [evidence], I think we'd be absolutely paralysed."

'Speed of light'

Every day the tribunal hears tales of torture, rape and mass murder. One official described the work as "scenes from hell, written on the darkest pages of human history."

Arbour: Has to stay detached

The work in bringing the perpetrators of war crimes to trial can seem a long, slow process. In the last five years only five people have been convicted by the tribunal.

However, Louise Arbour insisted the tribunal was achieving its goals. She is confident that justice can be done.

"I find it astonishing that we have to answer claims that this process is slow and so on, " she said.

Louise Arbour: "We're not going away"

"It's going at the speed of light compared to the way any criminal domestic system would capacity to deal with a fraction of the level of criminality that we're dealing with.

"It takes a lot longer to do justice than to commit the crime and at the end of the day I don't think its going to be the number of cases we have processed that's going to make the difference."

Difficult family life

Louise Arbour also spoke of her childhood growing up in French-speaking Quebec, life in a convent school, her family and her law career. She has to live away from her partner and family to work in the Hague and with two years left on the job she admitted it was sometimes difficult.

But Louise Arbour said she was motivated and ready to get on with the job.

"There are people who get out of bed every day and go and work in factories," she said "Their job takes a toll on their life a lot more than mine does."

You can hear the Hardtalk interview in full on BBC World and News 24 at the times shown below.

BBC World (times shown in GMT)
January 20 1530 and 1930
January 21 0730 and 0930