Should Chinese oil companies ultimately prove unreachable through the courts, there are other ways in which they can be held to account through their publicly-listed assets.
"The way people have tried to get at Chinese companies is not through the law but through capital market sanctions," said Arvind Ganesan, director of the business and human rights program for Human Rights Watch.
While the most obvious of these – de-listing companies from US stock exchanges – has not proved popular with legislators, grassroots action has been taken against Chinese firms in the past.
In 1999, China National Petroleum Corp (CNPC) announced plans to become the first Chinese state-owned enterprise to list on the New York Stock Exchange. But its plan to raise up to US$10 billion was undermined by claims that the proceeds could be used to perpetrate human rights abuses in a number of places, including Tibet and Sudan.
The bad PR forced CNPC into a rethink. A restructured deal saw the floatation of a CNPC subsidiary, PetroChina, which it was claimed would focus on China alone and not be linked to the parent company’s overseas assets.
CNPC remains PetroChina’s largest shareholder, though, and it could be argued that any income or debt passing between parent and subsidiary could ultimately be traced back to Sudan.
But Ganesan believes this grassroots-driven human rights agenda could be used to petition institutional investors not to back Chinese companies involved in countries such as Sudan.
"People don’t just throw up their hands and give up. Things evolve and institutions are held accountable."
The bottom line is that a growing number of – generally Western – investors have ethical as well as financial expectations of the companies in which they put their money.
"Corporations that operate in such countries must appreciate that they may be held to scrutiny by the public, whether it is the media, courts or court of public opinion," said Stephen Whinston, a partner at law firm Berger & Montague.