Clive Stafford Smith, a British-American attorney representing several detainees, said the findings indicate that innocent men were jailed and that the term "continued detention" is part of "a politically motivated farce."
"The Bush Administration wants to be able to say that these are dangerous terrorists who are going to be confined upon their release ... although there is no evidence against many of them," he said.
When four Britons were sent home from Guantanamo in January last year, Britain said it would detain and investigate them -- then released them after only 18 hours. Five Britons repatriated earlier were also rapidly released with no charges.
Murat Kurnaz, a German-born Turkish citizen, was also quickly freed when he was flown to Germany in August, bound hand and foot, after more than four years at Guantanamo.
US officials maintained he was a member of al-Qaeda, based on what they said was secret evidence. But his New Jersey-based lawyer, Baher Azmy, said he was shown the classified evidence and was shocked to find how unpersuasive it was.
"It contains five or six statements exonerating him," Azmy said.
In October, German prosecutors said they found no evidence that Kurnaz had links to Islamic radicals and formally dropped their investigation.
Insistent
The US insists that the fact that so many of the former detainees have been freed by other countries doesn't mean they weren't dangerous.
"They were part of Taliban, al-Qaeda, or associated forces that are engaged in hostilities against the United States or its coalition partners," said Navy Commander Jeffrey Gordon, a Pentagon spokesman.
But Joshua Colangelo-Bryan, a lawyer representing several detainees, said the fact that hundreds of men have been released belies their characterization by Secretary of Defense Donald Rumsfeld as "among the most dangerous, best-trained, vicious killers on the face of the earth."
"After all, it would simply be incredible to suggest that the United States has voluntarily released such `vicious killers' or that such men had been miraculously reformed at Guantanamo," Colangelo-Bryan said.
A senior US State Department official acknowledged that: "We do not ask countries to detain them on our behalf, so when a decision is made by a country to move forward with an investigation for prosecution, that is something they have decided to do pursuant to their own domestic law."
Requesting anonymity because she is not authorized to speak on the record, she said about 15 former detainees returned to the battlefield after being freed.
"That's the risk that goes along with transferring people out of Guantanamo," she said. "It's not foolproof."
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