WASHINGTON -- Most of the 595 suspected terrorists detained by the United States at Guantanamo Bay, Cuba, will be held indefinitely, even though there is not yet enough evidence to charge them with crimes, a senior Pentagon official said in an interview with the Globe.

The accounting by Paul W. Butler, special assistant to Secretary of Defense Donald H. Rumsfeld, was the first acknowledgment by the government that hundreds of detainees will probably be held without facing military tribunals. Officials have spoken publicly about the prospect of indefinite detentions for some, but they had not disclosed that the majority could be held until the war on terrorism is finished. Unless the US Supreme Court intervenes, the Bush administration plans to hold the prisoners who it believes are dangerous or who can provide useful information in fighting Al Qaeda and other terrorist groups.

''What I'm saying is that there is a large percentage right now who are either high threat or high intelligence value, that right now there's no intention to try them before a military commission," Butler told the Globe. ''They're dangerous. And we have a responsibility, both to our forces . . . and the rest of the world, to not let those people back out."

Butler and other officials also described the factors that are being used to assess how dangerous a detainee might be (joining Al Qaeda after Sept. 11, 2001, for example, might be worse than joining earlier); the interrogation booths at Guantanamo (Arabic posters on the wall encourage confession as a ticket home); and the difficult negotiations with more than 40 countries to take back some of the detainees (if the countries agree to US terms). The officials discussed for the first time the military's Criminal Investigation Task Force, which has interrogated detainees and followed leads around the globe to find evidence of guilt or innocence.

Butler expressed frustration that the United States has not gotten the word out about the investigations, that painstaking action is taken for inaction. ''One of the things that doesn't seem to come across is that there is this extensive process to try to figure out who these detainees are, what kind of intelligence they have, what threat they represent, and to treat them accordingly," Butler said in the interview Thursday in Rumsfeld's suite at the Pentagon. ''We're not in the business of just holding people for the sake of it. . . . We realize that we can't do that. We have to have justifiable reasons to hold on to people."

Butler's assurances did not persuade lawyers representing some of the detainees before the Supreme Court, where arguments will continue this week on the limits of the president's authority in the war on terrorism. Two of the lawyers said they were not surprised to hear that the government plans to hold so many people without trial or access to attorneys -- they had noticed that the government had not hired enough attorneys to handle hundreds of prosecutions -- but they said it confirms their worst fear.

''It's shocking to anyone who believes in the rule of law," said Michael Ratner, an attorney for several detainees with cases before the court. ''Indefinite detention without any legitimate court process is unheard of in this country."

Of the approximately 8,000 to 10,000 detainees scooped up in Afghanistan and Pakistan, about 738 were shipped to the US naval base in Cuba. The United States has released 131 and transferred 12 others to their home countries for detention. Of the remaining 595, only two have been charged with crimes so far. More detainees will be charged, Butler said. Some have been at Guantanamo since January 2002.

''In a traditional investigation, you show up at a crime scene, you grab some evidence, and you go try to find a suspect," said Colonel Brittain P. Mallow, commander of the investigation task force, whose 150-plus members were drawn from every military investigative agency. ''What we have is a pool of suspects, and the United States has asked us, 'What have they done, and have they done something that's worthy of prosecution?' . . . This has been one of the great lessons we've learned, how complex these cases are, and how time consuming it is to gather the facts on them and be able to prove them."

The first obstacle was establishing a detainee's true name and date of birth, even his home country. Some who claimed to be Yemenis turned out to be Saudis, or vice versa. They were arrested without passports, cellphones, or calling cards. Some were turned in by Afghans who were paid bounty in the search for Taliban and Al Qaeda members. Even the ''pocket litter," the money or scraps of paper that a police officer finds on a suspect, may have been scattered by Northern Alliance troops who handed over a prisoner. ''With a lot of these detainees," Butler said, ''everything you know about them comes from what they tell you or what someone else in the camp tells you."

In the interrogation booths at Guantanamo, they can see only glimpses of home, in the form of posters of a Middle Eastern oasis, with Arabic implorations such as, ''Daddy, please tell them what you know and come home."

The detainees speak eight major languages, and 20 or more dialects. The need for translators raised a question of who should sit where. ''In the early days, an uninitiated investigator would have the interpreter facing the subject and talking to him, perhaps across a table, and the investigator would be sitting over to the side with notes, feeding the translator the questions," said Mallow, a career Army officer and Middle East specialist. But that seating arrangement makes the translator the person in control. ''If I'm going to ask you questions, I want to face you. I want to establish contact with you, even if I'm not speaking your language. And so the interpreter may sit behind you."

Each detainee is rated in three areas: intelligence value, threat, and potential for prosecution. A rating above the minimum in any category can keep a detainee at Guantanamo. The facts gathered by interrogators and analysts are supplemented by reports from behavioral scientists. This task force, or CITF, is separate from Joint Task Force Guantanamo, or JTF GTMO, the more public unit that runs that Camp Delta prison and also interrogates the detainees for intelligence information to prevent future attacks.

The officials would not say exactly what benchmarks they use to calculate a detainee's threat rating. But some of the indicators include the extent of contact with senior Al Qaeda officials; special skills or training (Butler has described one unnamed detainee as a shoe bomb designer); financing (''if someone was captured with $3,500 in cash, US bills, that would be what we would call a clue," Mallow said); deception during interrogation, which is known to be part of Al Qaeda training; and commitment to holy war against Americans, either before or after the attacks of Sept. 11.

''Someone who joined the cause after 9/11, that might mean something, particularly if they admit to us, or somebody else admits to us, the reason they came is to fight the Americans -- they came to join the jihad," Mallow said.

Even after two years, the detainees continue to help investigators learn a great deal about Al Qaeda and a web of affiliated terrorist groups, the officials said. How was the detainee recruited, at a mosque or university? How did he get in touch with the person who knew where the safehouse was? How does one become a bodyguard for Osama bin Laden? How are nonprofit groups used in financing terrorism? How do leaders communicate orders?

''Actual operational, tactical information does wane as time goes by," Butler said. ''But we're looking at a broader goal here, trying to understand how these terrorist networks operate, how they morph."

For the detainees judged to be less dangerous, or those whose intelligence value has been exploited, some of the delay in releasing them is caused by the complicated negotiations with more than 40 countries to take back their citizens, Butler said. In some cases, the United States insists that the person be detained in the home country, but that may not be possible under that country's laws. Or the detainee could face a trial back home, except that evidence gathered at Guantanamo may not be usable in that country's courts. The closer another country's legal system is modeled on the US Constitution, the less likely it is to be able to use evidence gathered at Guantanamo.

''Most of the statements that we've gotten from someone -- if you're dealing with countries that have a Miranda-type law -- are inadmissible, and so what do you have?" said Butler, a former federal prosecutor who worked on the embassy bombings case against bin Laden before becoming responsible for detainee operations and other special operations at the Pentagon. ''We don't want to be in the business of just turning people back to a country to have them let go."

There's also the reverse situation, countries where the United States might fear for the safety of the detainees if they're shipped home. One case involves China and the Uighurs, an ethnic group of Muslims living mostly in northwestern China. The United States picked up more than two dozen Uighurs at the Afghan camps, where apparently they hoped to learn how to fight for independence from China. The United States no longer considers them a threat, and has negotiated with China about returning them. But Uighur exiles in the United States say that China can be expected to torture and execute the detainees, as it has executed other suspected separatists. This has put Human Rights Watch in the odd situation of campaigning for the release of most detainees, but against the release of these detainees. Butler said that any country receiving a detainee must agree to treat him humanely.

Each detainee has been photographed, fingerprinted, and swabbed for a DNA sample. The great fear, the officials said, is that they will release a prisoner, and then find his DNA on the wall of a bombed nightclub in Kuala Lumpur -- or a Starbucks in Columbus, Ohio. Each released detainee is added to the watch lists of people not to be allowed into the United States.

The Bush administration has contended that it has sufficient authority to hold the detainees as enemy combatants, not prisoners of war, because they did not fight according to the Geneva Conventions and therefore cannot benefit from its protections. The government says that the prisoners have been treated more humanely than international law requires. And Rumsfeld has said that detainees not put on trial will be able to meet annually with a military review board, although its rules have not been finished.

Tom Wilner, a lawyer who argued last week at the Supreme Court on behalf of 12 Kuwaitis who want judicial review of their detention, said he was glad to see the government confirming that most detainees won't go on trial. He has been trying to focus more attention on those detainees, he said, but the press and public have mostly thought of the process as one in which most detainees will either be convicted or acquitted. ''The ones who get a trial are the lucky ones," Wilner said. ''My 12 guys will never go before a tribunal, because they have no evidence against them."

Some detainees are cooperative, and some have hardly said a word in two years. Some seem to have been radicalized by their long detention, the officials said, and others seem to have been mollified by contact with Americans, even Americans who are their jailers, and by medical care and literacy programs at Guantanamo.

''I've heard everything," Mallow said, ''from 'I just want to go back and be with my family' to 'I'd kill you today if I could get out of this chair.' "

© Copyright 2004 The New York Times Company

###