Charles Crawford: Belgrade must accept history and finally confront need for action on Srebrenica

Belgrade is having a gloomy time in foreign courts. First the International Court of Justice last week gave an advisory opinion on Kosovo's 2008 independence declaration which was widely seen as a significant victory for Kosovo.

Now Judge Timothy Workman has not so much quashed as squashed Serbia's attempt to get former Bosnia leader Ejup Ganic extradited to Belgrade to face war crimes charges arising from the infamous Dobrovoljacka Street shootings in Sarajevo back in 1992.

The attack by pro-Bosnia forces on the Yugoslav Army convoy as it attempted to leave Sarajevo under UN protection on 3 May 1992 was dishonourable and a crime.

But are all dishonourable crimes equal? Belgrade's application in London looked like a weird attempt to cover everything in political slime to make a specious Serbia-favouring syllogism: All slimy people are guilty; all involved in the Yugoslav imbroglio were equally slimy; therefore all were equally guilty – and, by the way, equally innocent.

This sits (putting it mildly) uneasily with the facts. As the largest former Yugoslav republic, Serbia could have defined the region's future by insisting on reform and democracy. Instead Milosevic used Serbia's weight violently to lunge towards new ethnic facts on the ground.

Now what? Not much. The sullen on/off relationship between Belgrade and Sarajevo will drag on, with Republika Srpska leaders in Banja Luka eyeing Kosovo and manoeuvring against political integration with Sarajevo. Local war crimes trials will continue, not without success. Business, cultural and other links across the region will grow. Nothing is ever really settled in this region.

English law draws on Latin maxims. One is ex turpi causa non oritur actio – "no action arises from a dishonorable cause". Or, in plain English, "wipe your boots before coming into this courtroom".

President Tadic in Belgrade needs to wipe Serbia's boots, and end the discredited Belgrade policy of "relativising" the origins of the 1990s conflicts. That means arresting General Mladic and confronting the greatest European war crime of modern times, namely the 1995 Srebrenica massacres.

Charles Crawford is a former UK ambassador to Belgrade