Earlier this month, the National Human Rights Commission (NHRC) issued a momentous report on the Thai-Malaysian pipeline incident of 20 December last year. It's momentous because it's the Commission's first public challenge to government.

The NHRC is the most problematic of the independent bodies established by the 1997 constitution. Although the constitution's intentions were very clear, conservatives tried to emasculate the Commission in the subsidiary legislation. The members of the Commission are hugely worthy and high-powered, but without any tradition of such a body, they have had difficulty reaching agreement and asserting their role. Unlike other new "independent bodies", the NHRC has no judicial power, only the opportunity to make a lot of noise. While the NHRC was established in the Clinton era when the US promoted human rights, we are now in the Bush era with the US trampling on human rights at home and abroad, and sending messages to countries (like Thailand) which traditionally respond to such signals.

But the pipeline issue has given the NHRC a focus.

The events of 20 December 2002 outside the JB hotel in Hat Yai are, of course, not totally clear. But a good guess is that the police (or someone) decided to provoke an incident so they could arrest NGO leaders and discredit the pipeline protest in the eyes of the public. As soon as the incident happened, the Interior Minister fronted a press conference to claim the protest was led by "anarchists". The plan seemed to be working.

It was tripped up by a video camera which recorded the whole incident with its time counter running. Anyone who has seen that recording can start to guess the plot. A Martian asked to identify which of the sides were the "anarchists" would probably pick the police.

The NHRC report is a model of discretion. It describes the build-up to the incident in such a way that the reader understands the protesters were drawn into a trap, though the report draws no such explicit conclusion. It notes the police were signalled to move forward with shields and batons, resulting in injuries to both police and protesters, but avoids any description of police beating people and overturning trucks. But when the report reaches its conclusions, it is forthright and wide-ranging:

"a. The fact that government did not give people and communities the opportunity in this project to participate in the decision-making, management, conservation, and utilisation in a balanced and sustainable fashion of natural resources and the environment is in contravention of the 1997 Constitution of Thailand clauses 46, 56, 58, 59, 60, 76 and 79.

b. Government's use of force to disperse the demonstration while demonstrators were exercising their rights and freedoms to demonstrate peacefully and without arms, in the absence of any evidence or reasons to indicate that the demonstrators had or would use force to breach the police barrier, was an unnecessary use of force resulting in injury of demonstrators and destruction of property, in contravention of the 1997 Constitution of Thailand clauses 31, 44 and 48.

c. The fact that the police did not notify the accused of the charges and details of arrest, denied them access to lawyers, initially did not inform relatives of the arrest, prohibited relatives from visiting the accused, and prevented lawyers attending during interrogation, are violations of the rights of those arrested and accused under the 1997 Constitution of Thailand clauses 237, 239 and 241."

The report's recommendations are no less direct:

"1. To mitigate the immediate damage to the demonstrators resulting from violations of their constitutional rights, compensation for injury to body, mind and property should be made within 30 days, including the lifting of all cases against the demonstrators.

2. To prevent any future recurrence of such violence and violation of the people's constitutional rights and freedoms, the NHRC again calls on government to form an independent commission to thoroughly investigate the facts of the incident, form guidelines for people who exercise their constitutional right to demonstrate, and define the roles and responsibilities of government officials involved at all levels from policy through command to implementation. If during this investigation anyone is found at fault, then that person should show responsibility and be punished accordingly."

In short, the NHRC is saying: the government contravened thirteen clauses of the Constitution; it should accept responsibility, drop the cases, pay compensation, punish those involved, and learn from the experience. The NHRC has dropped a bomb.

The government's response it to play dead and hope the bomb is a dud. In the immediate aftermath of the incident, Thaksin suggested "don't re-elect me" if people disagreed with his handling of the pipeline, and said it would be a "grave sin" if activists talked to the UN human rights body about the incident. But since then, the government has dug in. The Interior Minister and police chief refused to cooperate with the NHRC inquiry. The release of the NHRC report has been met by a deafening silence.

Probably the government thinks that if this NHRC bomb does turn out to be a dud, then it will conclusively prove the NHRC is ineffectual, and will send a message to protesters that the Hat Yai incident is a good example of what they can expect.

But that is a high-stakes strategy. The Senate's investigation has reviewed the same evidence and reached similar conclusions. As the NHRC's listing of violated clauses indicates, this incident is a test case for many of the key principles of the constitution - community rights on local resources, people's rights to demonstrate, and human rights in the judicial process. The unwritten sub-text of the NHRC report accuses the police and Interior Ministry of acting in the bad old dictatorial ways. A lot more than a few broken heads, bashed trucks, and bad court cases are at stake. And because of that, the bomb probably will go off, not with an immediate bang, but eventually with the same impact.