Genocide: A difficult charge to prove

LONDON, England (CNN) -- Radislav Krstic's genocide conviction is the first handed down by The International Criminal Tribunal for the Former Yugoslavia.

A 1948 U.N. convention defines genocide as "the intent to destroy, in whole or in part, a national, ethnical, racial or religious group."

Those acts include murder, inflicting living conditions designed to eliminate a group, preventing births, or transferring children from one group to another.

To prove genocide, judges have to be satisfied that the killings in Srebrenica were systematic, organised and planned.

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There is no guidance as to the number of deaths required to satisfy the ''in part'' criteria.

Before Krstic's conviction, judges at The Hague had twice acquitted suspects on genocide charges, which carry a sentence of up to life imprisonment.

Bosnian Serb former camp commander Dusko Sikirica was cleared of genocide in June.

Former farm mechanic Goran Jelisic, who styled himself the "Serb Adolf Hitler," was cleared of genocide in 1999 -- although he was sentenced to 40 years for crimes against humanity. Appeals judges ruled that faulty genocide standards had been used.

Bosnian Serb Milan Kovacevic, accused of setting up prison camps, also went on trial for genocide, but died of a heart attack in 1998 before proceedings were completed.

A conviction in the case of of Radislav Krstic means atrocities committed in the Bosnian war will be classified as the first genocide in Europe since the persecution of Jews during World War II.

The Yugoslav court was established in 1993 to punish those responsible for atrocities during the break up of Yugoslavia after the start of war in 1991.

The Rwanda tribunal in Arusha, Tanzania, has passed down genocide convictions -- the court's harshest crime -- and handed down sentences of up to life imprisonment.