The decision to request arrest warrants against senior figures in the Libyan regime shows how international justice could become part of the Arab spring, writes Graham Usher at the United Nations On 4 May the chief prosecutor of the International Criminal Court (ICC) said he had "reasonable grounds" to seek arrest warrants against three Libyans who seem to bear "the greatest responsibility" for crimes against humanity (CAH) by Muammar Gaddafi's security forces during the Libyan uprising. Briefing the UN Security Council in New York, the prosecutor, Luis Moreno-Ocampo, did not name the three. But they were among those who "ordered, incited, financed or otherwise planned the commission of the alleged crimes". That suggests very senior officials in the Libyan regime, including perhaps Gaddafi and/or his sons, said UN envoys and Human Rights organisations. Moreno-Ocampo said he was also investigating war crimes and would not rule out future cases against attacks by NATO or rebel forces in Libya. "I don't care about the political colours. No one can attack civilians." For ICC judges to issue arrest warrants for CAH, violations must be systematic or widespread. Moreno-Ocampo said he had "strong evidence" of both. "War crimes are apparently committed as a matter of policy," he said. "The evidence shows events in neighbouring Egypt and Tunisia prompted Libyan security forces to begin preparations for the possibility of demonstrations in Libya. As early as January, mercenaries were being hired and brought into Libya." In February, before the conflict became armed, at least 500-700 civilians were killed by government forces, he said. "The shooting at peaceful protesters was systematic, following the same modus operandi in multiple locations and executed through the security forces. The persecution appears to be also systematic and implemented in different cities." He said rebel forces may also have engaged in "the unlawful arrest, mistreatment and killings of Sub-Saharan Africans perceived to be mercenaries. Reportedly angry mobs of protesters assaulted Sub-Saharan Africans in [the rebel-held] Benghazi and other cities and killed dozens of them." The Security Council welcomed his report, though with less zeal than when it had referred Libya to the ICC for alleged war crimes in February. Much play was made then that this was the first time the council had unanimously referred a state to The Hague. (In 2005 Sudan was referred for alleged war crimes in Darfur, but the US, Russia and China -- SC permanent members not parties to the Rome Statue -- abstained. But the unanimity was only skin deep, concealing a multitude of motives. Britain and France appeared to seek ICC involvement to grant legitimacy to any future military intervention in Libya (eventually approved in March in a subsequent council resolution authorising a no-fly zone over Libya. The US hoped the spectre of ICC prosecution would spur defections among Gaddafi's inner circle and so speed his ouster. And Russia and China -- hostile to foreign intervention just about anywhere -- hoped an ICC bluff would halt the drift to war. Three months on war has become fact, defections are few, Gaddafi is entrenched and NATO is seeking all the cover it can muster for air strikes that are legally questionable and smack of mission creep. Where there had been council unity on Libya, now there are splits and recrimination. United States Ambassador to the UN Susan Rice said the chief prosecutor's report showed "Gaddafi had lost all and any legitimacy." Russian Ambassador Vitaly Churkin said it showed "violence can only be halted through an immediate ceasefire and political settlement." Russia has long charged that NATO air strikes exceed the council's mandate of protecting civilians. "Divisions in the council shouldn't impact the ICC's work but I fear they might," said Richard Dicker, director of the International Justice Programme at Human Rights Watch. This could happen should the ICC actually issue arrest warrants, and call on the council to pressure the Libyan authorities to comply. That may be tricky in a council where the US, UK and France openly call for regime change but the other member states don't recognise the rebels. Human rights lawyers are also sceptical that Moreno-Ocampo's evidence for CAH is as strong as he suggests. In New York he spoke of a "predetermined plan" decided in "meetings" in Tripoli in January to crush the uprising before it threatened the regime. But for that to stick the prosecutor "would need more than crime-scene evidence," said a source. "He would need insider testimony from someone at the meetings, preferably a senior official. Without that I don't think Ocampo's case for CAH will survive the scrutiny of the ICC judges." But if arrest warrants are issued, there is little the council can do to reverse the ICC process, said Dicker. "Unlike travel bans or no-fly zones, justice can't be dialed down to suit the political needs of the moment. The council's unanimous referral to the ICC laid down a marker on accountability for horrific crimes in Libya and council members are on the line to make good on it." Nor will the glacial spread of the ICC's universal jurisdiction halt at Tripoli. United Kingdom Ambassador to the UN Mark Lyall-Grant said his country supported the ICC's mandate to fight impunity. But he wasn't referring only to Libya. He was referring to another Arab dictatorship. "The violent repression [in Syria] must stop immediately," he said. "The Syrian government has a responsibility to protect peaceful protesters, not attack them. We must be prepared to consider the appropriate avenues, including the ICC, to bring justice to the victims of these crimes."