Senators John McCain, Maria Cantwell and Lindsay Graham visited Guantanamo this week. Their conclusion, set out in a letter to Rumsfeld: Try them or free them.

[McCain] said in an interview that he believed the continued detention of the prisoners violated basic human rights precepts. "They may not have any rights under the Geneva Conventions as far as I'm concerned," said the senator, an Arizona Republican, "but they have rights under various human rights declarations. And one of them is the right not to be detained indefinitely."

McCain also said:

....a senior administration official told him before the trip that the military has been unable to develop cases against as many as a third of the detainees and that they will have to be released..... [McCain] "blamed bureaucratic gridlock for the pace of administration decision making."

So far all of the detainees were arrested in Afganistan and all are male. But...the first female prisoner is set to arrive this week.

The three 13 to 15 year olds we've heard about are still there:

Three of the detainees are aged 13 to 15 who were "kidnapped into" a terrorist organization and treated brutally, Graham said. He said they are slated for discharge early next year into the custody of United Nations officials who have organized a special program for child combatants.

The U.S. says there are three criteria for a prisoner's release:

He must be judged to pose no threat to the United States, to be incapable of providing further intelligence information and to have been uninvolved in criminal activity.

While 88 have been released to date, no more releases are currently scheduled. Details about the 88 (and the 20 new arrivals who replaced some of them) are here.

Update: Thanks to an astute commenter, it appears John McCain and Lindsay Graham were incorrect in their statement to the Washington Post that all of the detainees at Guantanamo are from Afganistan. At least six were kidnapped from a Sarajevo prison by Bosnian police, handed over to the U.S. and brought there after the Bosnian Supreme Court had ordered them released.