The Bush administration insists that it can hold American citizens in secret as long as it wants, without access to lawyers, simply by calling them "enemy combatants." A New York federal appeals court heard a challenge to that policy this week by the so-called dirty bomber, Jose Padilla. The administration's position makes a mockery of the Constitution and puts every American's liberty at risk. It is important that the court strike it down, and give Mr. Padilla the rights he has been denied.

Mr. Padilla is an American citizen who was taken into custody in Chicago in May 2002. The government suspects him of being part of a "dirty bomb" plot by Al Qaeda, but it has not charged him. Instead, it has labeled him an enemy combatant and locked him up in a naval brig in South Carolina. He has been held there nearly 18 months, with no indication of when he will be tried or released. He has not been allowed to meet with a lawyer, despite a lower court ruling that he should be.

Of all the post-Sept. 11 denials of civil liberties, the enemy combatant doctrine is among the worst. It gives the president untrammeled authority to lock up Americans merely by asserting that they are part of a terrorist plot. In its argument to the United States Court of Appeals for the Second Circuit this week, the government insisted that military-style rules like the enemy combatant doctrine now apply to American citizens, even on American soil, because Al Qaeda has "made the battlefield the United States."

Governments are always tempted to detain perceived enemies without charges, hold them incommunicado and deny them counsel. But the framers of the Constitution knew that if the government was allowed to act on those impulses, the result would be tyranny. That is why they built into this nation's founding document the very rights the Bush administration is intent on taking away.

Fortunately, it appears from this week's argument that the appeals court panel saw through the administration's spurious justifications. "As terrible as 9/11 was,"` Judge Rosemary Pooler observed, "it didn't repeal the Constitution."