In Cambodia, a tribunal set up to try the leaders of the Khmer Rouge has triggered intense contest between competiting approaches to justice, each inextricably bound up in politics

The  Extraordinary Chambers in the Courts of Cambodia is only partly about bringing Khmer Rouge leaders to justice. It is also a site where emerging principles of global justice may be explored, validated and normalised.

For those interested in rights, it is a place where new modes of victim participation can be pioneered and developed. For critics of Prime Minister Hun Sen’s government, it offers a means of placing pressure on the regime by exposing its track record on corruption, interference in the judicial process and support for a culture of impunity.

For the government, the ECCC is an opportunity. The trials provide scope for grandstanding in the prime minister's default mode, criticising the very same international community that provides so much aid and support. The trials allow Hun Sen to blame the problems of present-day Cambodia upon a small bunch of ageing, ailing ex-Maoists, thereby diverting attention from his own administration. The adversarial proceedings take place largely between the court's Cambodian and international staff, between the Cambodian government and the UN, between victims and judges, and between ECCC insiders and the wider Cambodian population.

Cambodia has long proved resistant to international pressures. Since Hun Sen ousted Prince Norodom Ranariddh in 1997, the Cambodian People's Party has won three general elections, gradually suppressing political opposition and establishing a hybrid form of electoral authoritarianism. The response of the West – and Japan – has been to provide enormous levels of foreign aid, linked to Cambodian promises of greater transparency, openness, efficiency and reform.

Such support reflects growing anxiety about the influence of China, which has become a major donor country in the region. The ECCC represents, on one level, a form of political climate change – an attempt to subvert the legitimacy of the government and promote more liberal and democratic practices.

A crisis is looming over Cases 003 and 004, which Hun Sen appears intent on blocking. Without government support, the tribunal would collapse; it is entirely dependent on local staff, and without the Cambodian security forces no further arrests of defendants could be made. Indeed, the government could even free the existing prisoners at any time. Would the UN ever call Hun Sen's bluff? A hybrid tribunal to try former Khmer Rouge leaders, even an unsatisfactory one, serves the purposes of many stakeholders. Aborted trials when the tribunal's work had only just begun would be a huge loss of face all round, not to mention a massive waste of money.

But at what point would no trials look better than flawed trials? The classic liberal argument is that whatever the shortcomings of war crimes tribunals, they are still better than any of the obvious alternatives. Yet where such trials are not managed by liberal states but partially subcontracted to authoritarian regimes, such arguments are weakened. The ECCC looks set to become the first tribunal over which authoritarian practices gain a decisive upper hand. The ECCC is currently failing and it is time the UN seriously considered withdrawing its support.

The ECCC illustrates the political struggles that underpin war crimes tribunals. Parallel political 'trials' which place both the Hun Sen regime and the UN in the virtual dock are assuming greater importance than the trials themselves. The issues involved in emerging forms of global justice are too complex and important to be left in the hands of lawyers and academic legal specialists; they demand close scrutiny from domestic, comparative and international political perspectives.