DURHAM - The Bush administration has stopped ignoring Congress regarding the kind of military commissions that should be used to try detainees at Guantanamo Bay, but it does not appear to have stopped ignoring the Constitution.

In the midst of intense media focus on the compromise recently reached between the White House and Sens. Warner, McCain and Graham, we must not lose sight of a fundamental legal point that should inform the political resolution of this issue. The Constitution's guarantee of due process of law, not an impending congressional statute, will ultimately determine the legality of any future commissions.

This is clear from the court's decision last June in Hamdan v. Rumsfeld. The court there held 5-4, with Justice Kennedy in the majority, that the administration's previous commissions were illegal because they violated federal military law, which the court read as including part of the Geneva Conventions. After the decision, many in the media misreported the ruling, suggesting that the court held the commissions illegal only because Congress had failed to authorize them. In fact, the court concluded that Congress had by statute prohibited the commissions. It did not say that congressional approval was all that was required to "fix" them.

Yet the administration continues to proceed as if Congress is all that stands between it and the commissions it wants. Among other things, the recent agreement between the White House and the three senators would permit the admission into evidence of multiple hearsay and statements obtained by any means short of "torture." That generous standard includes even extreme coercion, which most respected military and civilian lawyers regard as notoriously unreliable.

These dimensions of the recent compromise are not just unwise. They are also constitutionally dubious. That is why the president and now Congress would be prudent to slow down and proceed with greater caution.

Both Justice Stevens' opinion in Hamdan (which was joined in full by three justices and in part by Justice Kennedy) and Kennedy's separate opinion are suffused with concerns about the fairness of the commissions previously established by the president. For example, Justice Stevens wrote for the court that a "striking feature of the rules governing Hamdan's commission is that...testimonial hearsay and evidence obtained through coercion [are] fully admissible." The court had no occasion to decide the constitutionality of these features, but it went out of its way to cast doubt upon them.

These concerns indicate that constitutional standards of due process of law will ultimately determine how much "relaxing" of longstanding judicial procedures the court will allow. The court's concerns about due process will not be satisfied if Congress merely passes a law authorizing the administration to do most of what it tried to do before the court intervened.

No one need take my word for it. Just read the opinion of the decisive fifth vote on the court. Kennedy wrote that "[i]f Congress, after due consideration, deems it appropriate to change the controlling statutes, in conformance with the Constitution and other laws, it has the power and prerogative to do so." He later reiterated that "[b]ecause Congress has prescribed these limits [on the president's authority]," Congress can change them, requiring a new analysis consistent with the Constitution and other governing laws."

The emphasis is mine, but the language is Kennedy's. Congress is just as bound by the Constitution as is the president. Accordingly, Congress cannot authorize the president to violate the Constitution. There is no escaping an eventual constitutional inquiry, and the current proposal on the table is constitutionally vulnerable.

The ball is now in the court of the president and Congress. But the Supreme Court will not passively accept whatever they come up with. That is not how the separation of powers works in our constitutional system. As Chief Justice Roberts might say, the "umpire" awaits.

After more than four years of detentions without trial at Guantanamo Bay, it would be most sensible at this point for the president and Congress to pass a law that is clearly constitutional. That way, our country would avoid more wasteful litigation for years to come, the likely result of which would be a judicial determination that the commissions are unconstitutional. The next president and Congress would not have to start over again, and military commissions at Guantanamo would finally be able to proceed on a secure moral and legal footing.

(Neil S. Siegel is assistant professor of law and political science at Duke Law School.)

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