The same measure also empowers the president to define torture. It's a sad legacy for America and its already-tarnished world image.
The new law - the Military Commissions Act of 2006 - establishes a system for trying suspects in military tribunals. It was enacted after the Supreme Court ruled last June that the administration plan for trials by military commissions violated U.S. and international law.
In effect, President Bush got all he wanted from a submissive GOP-dominated Congress and a few spineless Democratic lawmakers. The president on Tuesday did not issue his customary signing statement interpreting implementation of the law. He didn't have to because lawmakers on Capitol Hill had handed him total victory.
The far-reaching legislation gives Bush the right to decide what constitutes torture. The president has often said "we do not torture," despite evidence to the contrary - and photographs from the infamous Abu Ghraib prison as well.
The president also can set guidelines for interrogation of prisoners. White House spokesman Tony Snow declined to say whether "waterboarding" - in which detainees are made to feel they are drowning - would be permissible. Other question marks under the new law include deprivation of sleep and shackling a prisoner in one position for hours.
The law specifically bars blatant abuses including murder and rape and "cruel and inhuman" treatment. But it also permits the withholding of evidence from defendants in certain cases.
And it denies detainees the right to file habeas corpus petitions to challenge their detentions in federal courts. The tradition of habeas corpus dates back almost 800 years to the Magna Carta.
Under the new law, the president also has extraordinary powers to designate who is an illegal enemy combatant, which potentially subjects U.S. citizens and foreigners to indefinite detention with no power to appeal.
Bush is also allowed to interpret the Geneva Conventions on Humane Treatment of Prisoners of War.
Furthermore, the CIA apparently will be able to continue sending prisoners to secret prisons abroad and agents will have immunity from prosecution for their interrogation practices. Many Europeans who have lived under tyrannical regimes cannot believe the U.S. would submit to such questionable treatment of detainees.
Bush was beaming when he signed the bill on a table with a sign in front that read: "Protecting America."
Standing by his side was Vice President Dick Cheney, a prime mover in the administration's drive to enhance presidential power. Cheney's fine hand was evident in the writing of the legislation, which is bound to be challenged in the courts.
But right now those who voted for this law believe it will be help them in the November election. And Democrats who voted against it should watch out for a total GOP assault on their commitment to protecting America from terrorist attack.
Bush called the law a "vital tool" in the war on terror.
"It is a rare occasion when a president can sign a bill that he knows will save American lives," Bush said.
"We will answer brutal murder with patient justice," he added. "Those who kill the innocent will be held to account."
Critics see the new law as authorizing creation of a veritable Gulag.
The American Civil Liberties Union called the new law "one of the worst civil liberties measures in American history."
As ACLU Executive director Anthony D. Romero put it:
"The president can now, with the approval of Congress indefinitely hold people without charge, take away protections against horrific abuse, put people on trial based on hearsay evidence, authorize trials that can sentence people to death based on testimony literally beaten out of witnesses, and slam the courthouse door for habeas petitions,"
Romero added: "It is unconstitutional and un-American."
Bush contended that his policies on terror suspects did not require congressional approval, manifesting his apparent belief that the president is above the law. The Supreme Court proved him wrong.
Bush's order for warrantless wiretapping of Americans is yet another example of a presidential power grab.
Tom Malinowski, Washington director for Human Rights Watch, said Bush has been accused of "criminal torture in a way that could hurt America and come back to haunt our troops."
One of the reasons Bush sought a green light from the lawmakers is "to have Congress stand with him in the dock," Malinowski added.
The military commissions act is law. And all Americans will be tainted by it.