Evidence of torture and abuse in Iraq by British and US forces squarely places them in violation of the Geneva Conventions and subject to being prosecuted, writes Chris Stephen
Britain's Defence Secretary, Geoffrey Hoon, may end up in the dock of the International Criminal Court following revelations of torture in Iraq, but his American counterpart, Donald Rumsfeld, will not be joining him.
In common with all EU states, Britain is a full member of the ICC, which opened last year in The Hague, and which has the Geneva Conventions as the centrepiece of its law. The United States, however, is not a member, and is not subject to its rules.
The abuse of prisoners in Iraq that has been made public in testimony and through photographs in recent days seems to be a clear violation of Article 3 of the Geneva Conventions of 1949 and which cover the treatment of non-combatants.
This article, which was later enshrined in ICC law, makes it an offence not only to cause physical harm to non-combatants, but also "cruel treatment", "torture" and "outrages upon personal dignity, in particular humiliating and degrading treatment".
There is some confusion about the categories under which those in detention fall - are they, for instance, prisoners of war, or criminal suspects? But for the Geneva Conventions, the difference matters little: the Geneva Conventions protect all who are "persons taking no active part in hostilities", regardless of their status.
The part of the ICC rules which will be worrying London is Article 28 of the Rome Statute, the treaty that sets out ICC law. This covers "command responsibility" which, as the name implies, makes a commander responsible for the actions of his unit.
The important requirement of Article 28 is that a commander, on hearing that his unit is committing crimes, must take immediate steps to both prevent further crimes, and punish those responsible.
According to the Red Cross, perhaps the world's most authoritative human rights organisation, details of abuse in Iraqi jails by British troops were passed to London in February this year. Yet the abuses went unpunished and, it seems, unremarked, until they were leaked to the press earlier this month.
How high up the "command tree" responsibility will go is debatable, but it is could well include Geoff Hoon because he is the man responsible for the actions of the armed forces. British Prime Minister Tony Blair may also be covered.
(The doomsday scenario - although improbable - for British defence chiefs is that Queen Elizabeth could also face censure. She is not only head of state but the head of the armed forces, and service personnel swear an oath of obedience not to the government but to the crown. However, while the queen has de jure - or official - command of troops, it is likely that a court would find she does not have de facto or actual command of these formations.)
The International Criminal Court came into force last year and was originally planned in 1998, coming into being with the Rome Treaty of 1998. Its headquarters is in The Hague and its powers are similar to those of the other Hague war crimes court, run by the UN. Under Rome Statute rules, Britain is allowed to prosecute violations of the Geneva Conventions under its own laws, with the ICC stepping in only if Britain fails in its duty.
The catch, for London, is that the ICC decides if the British courts have done their duty. Thus it is no good putting the miscreants on trial and refusing to consider charges against their commanders. Unhappily for the Blair government, international courts, and in particular the UN's Hague Tribunal, now trying Slobodan Milosevic, have built a solid base of case law in the past 10 years dealing with command responsibility.
Most war crimes cases focus on leadership issues, and the ins and outs of command responsibility prosecutions have been tested in court and precedents established.
Hoon will find it is no defence to plead ignorance - as commander he has a duty to be kept fully informed of the actions of his troops. Likewise, there is no defence of "military necessity" - Britain is also a signatory to the Torture Convention which makes it an offence not just to cause pain but also to deprive prisoners of comfort and sleep.
Further, there is no defence in claiming that the people being tortured were themselves criminals - suspects up to and including Saddam are guaranteed rights under the Geneva Conventions. As regards the US, it appears that American troops have been engaging in still more widespread breaches of the Geneva Conventions, placing both Defence Secretary Donald Rumsfeld and the commander-in-chief George Bush in the firing line.
Rumsfeld appears to have come close to implicating himself when he told a congressional inquiry recently that he had reports of these abuses and that he knows of many additional abuses. Yet the Americans are not members of the International Criminal Court, and US officials are in the end answerable only to their own courts.
America is a signatory to the Geneva Conventions, and, on paper, its courts are bound to follow its rules. Yet US courts have so far failed to take action against the use of US armed forces in running Guantanamo Bay in Cuba, where sleep deprivation and other discomforts are widely practised and men are held without charge or access to lawyers.
In practice, if US courts fail to prosecute violations of the Geneva Conventions, there is no legal body empowered to overrule them. For Donald Rumsfeld, this is likely to mean he will not be prosecuted.
The Geneva Conventions, however, assert universal jurisdiction - in other words, nations signing them promise to prosecute violations even if neither the perpetrator nor the site of the offence are in their own territory. Under these provisions, France, for instance, could in theory arrest and try any of them should they arrive on a visit.
• Chris Stephen is author of Judgement Day: The trial of Slobodan Milosevic, to be published this summer by Atlantic books.