The US Attorney General Alberto Gonzales, a close friend of President George Bush and one of the most controversial members of the administration, resigned abruptly yesterday without explanation.
Mr Gonzales was the architect of the Bush administration's policy of placing detainees captured in the fight against terrorism beyond the protection of any law. His policies cleared the way for brutality against detainees in Iraq, Afghanistan, Guantanamo Bay and other secret "black site" prisons.
But his downfall came when critics said he lied under oath to Congress over the firing of nine US attorneys and for ordering the FBI to spy on Americans without court warrants.
Mr Gonzales, who came from humble origins to become the first Hispanic to lead the Justice Department announced his resignation in a brief press appearance in which he called his 13 years in government a "remarkable journey". Declaring that he had "lived the American dream," he gave no further clue about why he resigned after stonewalling his critics in Congress for months.
President Bush bitterly assailed those political enemies yesterday, saying they had treated his friend unfairly. Speaking from his Texas ranch, he said: "It's sad that we live in a time when a talented and honourable person like Alberto Gonzales is impeded from doing important work because his good name was dragged through the mud for political reasons."
Mr Bush has yet to pick a replacement but one man being named is Michael Chertoff, the Secretary of Homeland Security, a former federal judge. He recently raised eyebrows when he declared that he had a "gut instinct" that America was about to be attacked by terrorists on the scale of the 11 September 2001 attacks, once again.
As Attorney General, Mr Gonzales wrote much of the dubious legal advice underpinning the "war on terror". He justified the mistreatment and torture of terrorist suspects in Guantanamo Bay and other secret prisons and asserted that the Geneva Conventions did not apply to al-Qai'da and Taliban fighters captured in Afghanistan.
His departure from power, which was formalised over Sunday lunch at Mr Bush's Crawford ranch, means the last of the so-called Texas mafia who accompanied the President to Washington six-and-a-half years ago have gone. Two weeks ago, the presidential adviser Karl Rove announced he would be departing this weekend. There is now a palpable sense of power draining away from a beleaguered presidency, still with 18 months to run.
Considered by many to be one the worst US Attorney Generals in recent history, Mr Gonzales was even accused of perjuring himself before Congress. During testimony, he frequently said he could not remember key events about a secret government programme for spying on US citizens or the wholesale sackings of US attorneys because they were politically suspect.
As late as Sunday afternoon, Mr Gonzales' office was denying he had resigned, even though he told the President last Friday that he intended to do so.
Mr Bush has been unfailingly loyal to his inner circle of aides and officials stressed yesterday that he had accepted the resignation only grudgingly.
The Democrats tried to restrain any triumphalism yesterday but the New York senator Charles Schumer told the New York Times: "It has been a long and difficult struggle but at last the Attorney General has done the right thing. For the past six months, the Justice Department was virtually non-functional and desperately needs new leadership."
Much of the discussion about Mr Gonzales focused on his role in the dismissal of nine US attorneys last year in what was widely seen as a purge of officials who were even mildly critical of the White House.
But the Gonzales legacy may lie more in his wilful disregard for human rights law and his cavalier approach to the interrogation of detainees in the "war on terror". In a 2002 memo, he wrote that Article III of the Geneva Conventions was outdated. He derided as "quaint" the regulations requiring captured fighters to be given "commissary privileges, scrip, athletic uniforms, and scientific instruments".
He was also behind the controversial presidential order setting up military tribunals to try terror suspects rather than using civilian courts. Those tribunals have failed to achieve a single conviction so far and the continued operation of Guantanamo Bay has become a running sore for the administration in its relations with the outside world.
Of equal concern to Americans has been his use of the Justice Department and the FBI to improperly and possibly illegally use the USA Patriot Act to spy on US citizens. This month it was announced that information collected by America's network of spy satellites inside the country was being shared with law enforcement offices.