Nov. 11 (Bloomberg) -- Debate over the treatment of enemy combatants in U.S. custody has slowed passage of two major defense measures by the U.S. Congress.

Continuing amendments to the Senate's defense authorization bill -- including one yesterday to deny court challenges to detainees at Guantanamo Bay, Cuba -- forced the chamber to put off a final vote on the measure for a second straight day. This amendment, introduced by Lindsey Graham, a South Carolina Republican and former Air Force Judge Advocate General, would nullify a June 2004 Supreme Court ruling that Guantanamo detainees could challenge their detentions.

The authorization bill sets military policy and has become a vehicle for lawmakers' efforts to weigh in on the detainee issue. Graham's amendment joins one sponsored by John McCain of Arizona to ensure U.S. interrogation techniques don't violate the Geneva Convention and a third by Massachusetts Democrat John Kerry requiring the national intelligence director provide a classified report on any secret detention facilities.

Kerry's amendment was in response to a Washington Post report Nov. 2. that the CIA is hiding and interrogating some of its most important al-Qaeda captives at the secret prisons overseas. The sites are part of a program started almost four years ago and are known by only a handful of U.S. officials. The Bush administration has neither confirmed nor denied the report.

`Pretty Big Issue'

The McCain and Kerry measures passed by wide margins. Graham's passed by a vote of 49-42. Given that close vote, the import of the subject and its last-minute consideration, the Graham amendment likely faces modification, said Louis Fisher, senior specialist on the separation of powers for the nonpartisan Congressional Research Service.

``The McCain thing has been debated for such a long time that people have an understanding,'' Fisher said in an interview today. The Graham amendment, in contrast, ``came up quickly.''

``It's a pretty big issue; 49-42 is close; I don't know how much wiggle room there is in some of those votes,'' he said. ``It certainly takes away from the what the Supreme Court was saying.''

The debate on Graham's amendment resume Tuesday when the Senate picks up the bill, which authorizes $491 billion in defense spending.

The amendment, if also adopted by the House, would void any suits pending in U.S. courts as soon as the authorization measure becomes law. About 200 of about 500 detainees have filed habeas corpus motions, The New York Times said today.

Opposition

The amendment is opposed by a nonprofit organization of former and current military attorneys.

The amendment ``cannot be harmonized with our nation's longstanding adherence to the rule of law,'' Eugene Fidell, president of the National Institute of Military Justice, wrote Nov. 9 to Senate Judiciary Committee Chairman Arlen Specter of Pennsylvania.

Fiddell, in an interview today, said his organization rarely comments on pending legislation but felt compelled in this case.

The Senate ``should energize the amber warning light and proceed with caution a matter as serious and complicated as this,'' he said.

The defense authorization bill passed by the House also contains no language similar to the McCain or Kerry amendments, setting up confrontations when the two chambers negotiate a final, compromise measure.

Negotiations Stalled

The two chambers already are at odds over the McCain amendment's inclusion in the appropriations bill that funds the military. The House version has no language similar to McCain's amendment.

McCain's amendment was added to the defense appropriations bill Oct 6. and to the authorization bill Nov. 4. It's ``such an important item -- certainly in the Senate's mind -- that we have to put it in both places,'' Senate Armed Services Committee Chairman John Warner of Virginia said in an interview last week.

The House passed its defense appropriations bill in July, the Senate passed its Oct. 7. The two chambers still haven't met to negotiate a compromise, knowing the McCain amendment is a sticking point.

House Appropriations Committee Chairman Jerry Lewis of California said yesterday that, with the amendment on the Senate's defense authorization bill, it might not be needed in the compromise version. He said the House leadership hasn't decided this question.

``I'm not going to have it make or break our bill,'' Lewis said in an interview.

President George W. Bush threatened to veto the entire appropriations defense spending bill over McCain's amendment.

More recently, the White House offered to go along if Central Intelligence Agency agents working overseas were exempt from any restrictions.

To contact the reporter on this story: Tony Capaccio in Washington at acapaccio@bloomberg.net.

Last Updated: November 11, 2005 15:19 EST