THIS MONTH a federal appeals court overturned a lower court's decision halting the Bush administration's plans for military tribunals at Guantanamo Bay, Cuba. The earlier decision contained some legal errors, so the ruling was not a surprise. But the judgment has the effect of allowing the Bush administration to resume its ill-advised attempt to craft an almost entirely new justice system for enemy combatants accused of war crimes. The Pentagon announced that the tribunals, known as commissions, would resume as soon as possible.

The far better course would be to take a deep breath and a look at the big picture: Nearly four years after the attacks of Sept. 11, 2001, the military has failed to bring a single person to trial before the military commissions. When it finally does so, the trials will be an uncertain project in terms of both fairness and effectiveness. Meanwhile, the system for detaining and interrogating detainees before trial remains in a legal limbo that has led to serious abuses and caused enormous damage to America's global prestige. The administration's policy for foreign prisoners requires an across-the-board rethinking and close congressional collaboration.

The delay of trials was partly the result of the current litigation, and an appeal to the Supreme Court could stretch out the matter even longer. But it is wrong to blame the administration's problems on the federal courts. The administration invited trouble when it abandoned the Geneva Conventions and the Army interrogation manual as standards for detainees; instead of drawing on the well-established system of military trials known as courts-martial, it sought to revive the cruder and less protective commission process. Part of the reason for these decisions was the legitimate worry that certain rules of Geneva or of courts-martial would create dangerous difficulties in terrorism cases. But a big part of the policy was ideological, a commitment not to give accused terrorists more legal process than absolutely necessary.

There is an alternative, if the administration is wise enough to take it: Accept congressional involvement in setting the rules in exchange for the legitimacy that only the national legislature can confer. This would put the administration on far more solid legal footing and, in addition, could put society's stamp of approval on reasonable procedures both for classifying detainees and for bringing them to justice. Interest in playing a constructive role has grown in Congress in recent months. Senior Republican senators such as John W. Warner (Va.), Lindsey O. Graham (S.C.) and John McCain (Ariz.) are preparing legislation.

As a first step, Mr. McCain and Mr. Graham may propose language early this week as an amendment to the defense operations bill. Their measure would require all interrogations to be conducted according to the norms of the Army manual and forbid "cruel, inhumane and degrading" treatment of all foreign detainees. Currently, the administration contends that prisoners held by the CIA abroad may be subject to such abuse.

The GOP amendment could correct some of the most serious problems behind the continuing scandal over abuses of prisoners at Guantanamo, the Abu Ghraib prison in Iraq and elsewhere. Yet rather than work with the Republican senators, the White House is crudely threatening to veto the defense bill if it contains any language on prisoners. The administration's message is that Congress should have no say over how the United States questions or prosecutes the thousands of foreigners it is holding, including those on American bases. Just such highhandedness helped get the administration into the mess it faces with foreign detainees. Congress should insist on a different approach.