Today's sharpest House debate focused on a provision that would have allowed the government to deport alien criminals and terror suspects to nations that might torture them. Many such suspects, backers said, have been released in the United States because a court ruling bars their deportation or long-term incarceration. The House amended the provision to allow the secretary of homeland security to detain such suspects indefinitely.

The Supreme Court ruled a few years ago that indefinite detention for non-citizens who have gained entry into the U.S. is unconstitutional. Zadvydas v. Davis, 533 U.S. 678 (2001.)

Statute permitting indefinite detention of an alien raises a serious constitutional problem. The Fifth Amendment's Due Process Clause forbids the government to deprive any person of liberty without due process of law. Freedom from imprisonment -- from government custody, detention, or other forms of physical restraint -- lies at the heart of the liberty that Clause protects.

Government detention violates that Clause unless the detention is ordered in a criminal proceeding with adequate procedural protections, or, in certain special and narrow non-punitive circumstances, where a special justification, such as harm-threatening mental illness, outweighs the individual's constitutionally protected interest in avoiding physical restraint.

It will be interesting to see whether this provision passes legal muster, assuming it survives the conference. I can't say because I haven't read the amended House provision to see if Zayudas and its progeny apply.

The best course would be for the Senate conferees not to give in to the House conferees and to boot this and all the new law enforcment powers contained in the House bill. The conferees should pass only the reforms recommended by the 9/11 Commission and leave the rest for another day and another Congress.