NEW YORK -- REMARKABLY, President Bush has not learned any lessons from the excesses of his "war on terrorism," now in its sixth year. Even though the president's own secretaries of state and defense have warned that the prison at Guantánamo is undermining America's credibility, the president continues to assert the powers of a king by detaining people without charge and without court review whenever he deems them "enemy combatants." This strategy contradicts America's core values and undermines the fight against terrorism.

In 2004, the Supreme Court sensibly defined the term "enemy combatant" as an enemy solider who engages in combat against American troops on an actual battlefield. The court also ruled that the United States must provide a legitimate process to make sure we are detaining the right people, not innocent tourists, embedded journalists, or local aid workers swept up amid the chaos of war where mistakes are easily made.

The administration, nevertheless, has ignored these limits in three important ways. First, it has defined "enemy combatant" in terms so sweeping that it would allow the president to lock up a little old lady in Switzerland who gives money to a charity which, unbeknown to her, is secretly funneling money to terrorist organizations.

Second, it has failed to follow the Geneva Conventions and the U.S. military's own regulations which require a prompt hearing for detainees seized on the battlefield to separate innocent civilians from actual combatants. To make matters worse, only 5 percent of the detainees at Guantánamo were captured by U.S. forces; 86 percent were taken into custody by Pakistani or Afghan forces at a time when the U.S. was offering large financial bounties for the capture of any Arab terrorist.

And third, the administration has blocked review of its detention practices by denying habeas corpus, which requires a court to examine the factual and legal basis for a prisoner's confinement. As a result, the administration has prevented any judge from determining whether the individuals it has jailed are actually terrorists — a position that speaks volumes about the government's lack of confidence in its evidence.

Regrettably, last fall Congress increased, rather than curbed, the president's power grab by passing the Military Commissions Act. This act not only weakens longstanding rules against illegal detention and torture, but also prevents the federal courts from enforcing those rules by eliminating habeas corpus.

Unchecked executive detention has created a prison beyond the law at Guantánamo, where nearly four hundred individuals remain detained without charge or due process. Though labeled as the "worst of the worst," according to the government's own data, only 18 percent of the detainees at Guantánamo have any definitive affiliation with al-Qaida or the Taliban. But since the government never has to present its evidence in a court of law, errors go uncorrected.

The president's quest for ever greater power is not limited to Guantánamo, but extends to the United States. Mr. Bush maintains that he can jail without charge an individual living in this country, whether an American citizen or not. As a result, a college student whose former roommate later joins the Taliban, a chief executive who donates money to an organization he believes is helping to build hospitals in the Middle East or a person who teaches English to the child of an al-Qaida member, all may be permanently imprisoned as "enemy combatants" without any proof of guilt.

To be sure, it is difficult to imagine any judge tolerating this state of affairs. But the problem is that without habeas corpus no judge can ever review the government's evidence, leaving detainees to languish in prison based solely on executive say-so.

The issue is not whether the president acts in good-faith when he deprives people of their liberty. The genius of our Constitution is that it does not entrust any president with that awesome power but instead sets up a system of checks and balances that prevents any person from placing himself above the law.

The president's "trust-me" approach to civil liberties does not just defy America's best traditions. It robs the fight against terrorism of the legitimacy and credibility it needs to succeed.

Over the last five years, Guantánamo has become a lightning rod for criticism and short-hand for the abuse of power. Our closest allies have denounced Guantánamo as a "shocking affront to the principles of democracy," while Secretary of Defense Robert Gates recently called for the prison's closure.

Guantánamo makes it more difficult for America to demand that other countries obey the rules by showing we do not follow those rules ourselves. The same goes for the practice of "extraordinary rendition" in which the United States hands individuals over to countries like Syria and Egypt for torture. Like the detentions at Guantánamo, such practices put Americans at risk by encouraging other nations to treat our citizens as we have treated theirs.

The damage wrought by the administration's wrong-headed policies cannot be remedied overnight but will require a concerted effort to develop a rights-respecting approach to counter-terrorism. The first step is an easy and obvious one: Restore habeas corpus, the greatest safeguard of individual liberty and check upon arbitrary executive power.

Restoring habeas will demonstrate that America gives all prisoners a meaningful chance to prove their innocence. Nothing less can suffice in a country committed to due process and the rule of law.

Jonathan Hafetz directs litigation for the Liberty and National Security Project of the Brennan Center for Justice at New York University Law School, is counsel to several detainees and is writing a book on post-9/11 detentions to be published by NYU Press.

© 2007 The Providence Journal