US credibility in maintaining human rights is challenged by the report from Human Rights Watch, a leading independent watchdog on human rights, that demands the prosecution of Sudanese and American government officials linked to the mass slaughter in Darfur and the prisoner abuse scandals in the Iraqi Abu Ghraib prison and Guantanamo Bay.

The report issued by Human Rights Watch says the response to each of the scandals is crucial for the global fight for the protection of human rights.

"The vitality of global human rights depends on a firm response to each -- on stopping the Sudanese government’s slaughter in Darfur and on fully investigating and prosecuting all those responsible for torture and mistreatment in Iraq, Afghanistan and Guantanamo," it said.

So far only low-rank troops have been charged in the Abu Ghraib scandal that was tied to the shocking pictures of pyramids composed of naked men and US soldiers holding Arab detainees on leashes. Human Rights Watch claims the US is setting a bad example to other countries, as Russia, for instance, nods to the US practices as it blames Chechnya abuses on younger soldiers.

"The U.S. government is less and less able to push for justice abroad, because it’s unwilling to see justice done at home," said Kenneth Roth, executive director of the organization.

The Human Rights Watch report condemns "the world’s callous disregard" for the Darfur tragedy where 70,000 people died and 1.6 million more have been displaced in an armed conflict that started in 2003.

"The crimes committed in Darfur must not go unpunished," the report said, insisting on the use of the International Criminal Court to punish the responsible persons.