Corporations that exploit conflicts to illegally extract or purchase natural resources from war-torn countries should be charged with war crimes, a University of British Columbia professor argues in a document he hopes will encourage governments and prosecutors around the world to pursue such cases.

James Stewart, an expert on international crime, is in The Hague this week to present a legal manual for prosecuting companies that profit from diamonds, gold, oil and land and other resources during times of war.

He says corporations that profit from conflicts in places such as the Democratic Republic of the Congo and Liberia have typically been able to escape scrutiny for effectively financing rebel groups and brutal regimes that perpetuate violence.

"Blood diamonds are just the tip of the iceberg — it's blood tin, blood gold, blood timber, the list continues," says Stewart, himself a former war crimes prosecutor.

"Illegal exploitation of natural resources provides money for weapons transfers, which provides weapons for egregious human rights violations, which then in turn motivates local populations to illegally exploit natural resources. The key ingredient here is that certain companies play an indispensable part in this cycle."

Stewart argues companies that obtain natural resources from war zones, either by actively dealing with rebel groups or buying resources they know were extracted illegally, could be charged with the war crime of pillaging — which is essentially theft during war.

He points to a report from the United Nations into the removal of mineral and forest resources in the Democratic Republic of the Congo during the conflict in the African country.

The report named dozens of corporations, mostly Western-based, that were involved in extracting resources from the Congo. Those relationships helped fund the rebel Alliance of Democratic Forces for the Liberation of Congo-Zaire and enrich neighbouring countries that became involved in conflict that raged through much of the 1990s.

"These companies — and many common household name companies — are involved in the illegal exploitation of natural resources," says Stewart. "What makes it illegal is essentially the theft: they're buying or extracting resources from people who don't own the resources, often rebel groups, often notoriously brutal regimes."

Stewart says a number of corporations were successfully prosecuted following the Second World War for collaborating with the Germans to access resources in Nazi-occupied regions, but there have been virtually no similar cases since.

"In the modern era, with the rise of international prosecution, there hasn't been a similar interest in the companies that are facilitating atrocities," he says.

Stewart hopes his manual changes that.

The conference in The Hague — titled Corporate War Crimes: Prosecuting Pillage of Natural Resources — will be attended by prosecutors and war crimes investigators from around the world, including from the International Criminal Court and the International Court of Justice.

He says he's created the first comprehensive manual explaining how the current laws relate to corporations profiting from conflicts — and he predicts that will prompt courts to launch prosecutions against such companies.

"I think this provides a missing blueprint for dealing with resource wars that many, many people are interested in," he says.

The conference is sponsored by the Dutch and Canadian ministries of justice, the Open Society Justice Initiative, the University of British Columbia and Leiden University in the Netherlands.