The man who decides the fate of Guantanamo detainees
Matthew Olsen's task force is resolving the fate of Guantanamo's remaining inmates
Matthew G Olsen heads the US task force deciding the fate of the remaining detainees at Guantanamo Bay.
While hopes of meeting President Barack Obama's January 2010 deadline for closing the camp have ended, Mr Olsen and other US officials have been meeting at secure locations to try to resolve the outstanding cases.
The BBC's Jon Manel met him on the car journey from Washington DC to northern Virginia.
"So at this meeting this afternoon, you'll actually decide the fate of one or more of the Guantanamo detainees, will you?" I ask.
"That's correct" says Matt Olsen, checking his wing mirror.
We are stuck in heavy traffic on the George Washington Parkway. We have crossed the Potomac River but there are road works ahead. Mr Olsen has already made a quick call to warn he will be late. It is a familiar journey.
"We have a meeting every Wednesday. We review the cases of the detainees at Guantanamo and try to reach decisions about the appropriate disposition of each detainee."
Mr Olsen, who has been a lawyer with the Department of Justice for 12 years, works in the Attorney General's office. He was made Executive Director of the Guantanamo Review Task Force on 20 February 2009 - one of the key roles in President Obama's plan to close the detention centre.
The weekly Wednesday Review Panel considers recommendations made by the Task Force, often at a secure location in Virginia. The Task force consists of around 60 lawyers, analysts and agents - some from the intelligence agencies.
MATTHEW G OLSEN
Appointed executive director of the Guantanamo Review Task Force, February 2009.
Previously acting assistant Attorney General for the Justice Department's National Security Division.
Formerly, deputy assistant Attorney General, he helped to establish the National Security Division in 2006.
Served as the chief of the National Security Section of the US Attorney's Office for the District of Columbia.
Also worked as special counsel to the Director of the Federal Bureau of Investigation (FBI), working on national security policy.
For months, it has been painstakingly combing the files of all 242 men held in the controversial detention centre when President Obama came to office.
"We look at everything that we're able to obtain that is in the government's possession. And I should say that one of our initial challenges was collecting all that information."
It had been spread out amongst various agencies and departments.
"We actually established a secure network, a database status only accessible to our task force out at our government building".
The traffic is not really moving so it gives us a chance to speak about the how the crucial decisions are taken.
"We look at the questions of transfer and we look at the questions involving the possible prosecution of detainees."
I ask if it is a case of determining their guilt or innocence.
"It is more nuanced than that. What we are looking at is 'can this person be safely transferred out of the United States?'
"'Can they be transferred to a country that will be able to implement adequate mitigation measures to address any threat the detainee may pose?' It's a judgement on risk.
"And then with respect to prosecution," he adds, "there's the judgement on 'is there sufficient admissible evidence to pursue a prosecution?'"
The review panel, made up of senior officials from several US government departments, has to make unanimous decisions. Cases are considered at "cabinet level" if the panel fails to come to a conclusion.
The traffic has now cleared and we pull over in a lay-by. I had already been warned that I could only travel part of the way.
"It's classified. The meeting itself is a government deliberation," he explains.
We meet again the following morning. He sounds a bit croaky. Tired perhaps? He says he has a bit of a cold. It sounds like it was a successful meeting.
"We met for over three hours. We were able to resolve a significant number of cases."
Were they resolved for trial or release?
"We had a mix of cases yesterday - that's about as much as I can say. In some instances we weren't able to resolve [the cases] - we talk about a case but we identify an issue or a question that we want to go find out the answer to. And then we just postpone those cases for a week."
Some of the most difficult dilemmas have been about whether to return Guantanamo prisoners to Yemen, with fears this could be tantamount to sending them straight into the welcoming arms of al-Qaeda.
Two former Guantanamo detainees released to Saudi Arabia by the Bush administration are thought to be key al-Qaeda figures in Yemen. Just before Christmas following months of deliberations, six were sent back to Yemen.
"The situation with Yemen has been a situation that we've been aware of and had access to intelligence information from the outset of our process," Mr Olsen explains.
Umar Farouk Abdulmuttalab, the Nigerian man accused of trying to blow up an aeroplane on Christmas Day, is alleged to have trained in Yemen. So was sending the Guantanamo detainees back there a mistake?
There are still some 200 prisoners in the Guantanamo prison camp
"I'm not going to say whether it was a mistake or not I think that we are making the best possible judgements we can make based on a great deal of information.
"There's no precedent for what we've done in terms of collecting this information in one place - it didn't exist in one place before we started this process.
"No decision about any of these detainees is without some risk. We need to be clear about the fact that we're making predicted judgements at some level about whether somebody is going to pose a risk to us in the future if they are released.
"But I do think that what we are doing is bringing to bear the right people and the right approach to make those decisions in the best possible way."
For now, all future transfers to Yemen are suspended.
Matt Olsen's task force has approved the transfer of more than 100 Guantanamo prisoners to other countries and 42 have already gone. Around 40 are on a list to be tried, either in federal courts or revamped military commissions.
President Obama's one year deadline for the closure of the detention centre will not be met but the Department of Justice lawyer insists it has been vital.
"Having that one year deadline was absolutely critical for us. We needed to have a deadline because we are making difficult decisions that I think would be very hard to make in the absence of a date."
Closing Guantanamo was broadcast on BBC Radio 4 on Tuesday, 12 January 2010 at 2000 GMT, repeated 17 January 1700 GMT. You can also listen via the BBC iPlayeror download the podcast.
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