A Mauritanian man whose best-selling book provided a rare window into US prison life at Guantanamo Bay, Cuba and alleged torture tactics that have been shrouded in secrecy is asking a review board to clear him for release after 14 years of being held without charge.

Mohamedou Ould Slahi "understands his past mistakes", denounces any forms of "violent jihad", and has "never taken any hostile action" against the United States, according to his lawyers.

The US alleges that Slahi, 45, swore an oath to al-Qaeda and was a recruiter who also helped to facilitate the travel of alleged September 11 attacks planner Ramzi bin al-Shibh, currently in Guantanamo, and two other 9/11 hijackers.

Retired Colonel Morris Davis, a former chief prosecutor for the Guantanamo Bay military commissions - who years ago met Slahi and examined his case closely - told Al Jazeera he could find no grounds on which to charge Slahi with any offence.

"He's spent a long time in confinement for someone [for whom] there is no evidence that he committed a crime," Davis said.



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In 2011, with a legal binding executive order, President Barack Obama directed that Guantanamo prisoners who were not charged and not cleared for transfer had their cases reviewed by the Periodic Review Board (PRB) in a year's time.

Five years later, however, dozens of men still have not had a chance to plead their cases. On Thursday Slahi, who has not been charged with a crime, finally will.

Slahi's journey to Guantanamo

He comes from a family of 12 children. At age 18, Slahi travelled to Germany on a scholarship to study engineering. From Europe in the early 1990s, he navigated his way to Afghanistan, becoming part of the network of al-Qaeda units that were then fighting against the Soviet-backed government - as were the Americans.

But in 1992, he said he cut off his connections with Osama bin Laden's group and returned to Europe, completed his studies, and went to work in Germany and later in Canada, eventually returning home to Mauritania in 2000.

In late September 2001, Slahi was briefly arrested by Mauritanian authorities and questioned by the FBI about the so-called "Millennium Plot" to bomb Los Angeles International Airport.

The Mauritanians declared him innocent. But in November 2001 Slahi was asked to report to the police station in Nouakchott. He did so voluntarily, thinking he would be home by the day's end. Slahi was then betrayed. The CIA rendered him to Amman, Jordan, beginning his "world tour" which later saw his extrajudicial transfer to Bagram Air Base in Afghanistan, and eventually to Guantanamo, where he arrived on August 5, 2002.

Court order for Slahi's release

Donald Rumsfeld, the former US defence chief, personally approved Slahi's "special interrogation techniques", because the Mauritanian was considered a high-value detainee.

Slahi's best-selling book Guantanamo Diary recounts his interrogations and alleged torture.

Prisoner 760, as he has been identified by his captors, writes of being sleep-deprived, subjected to extreme temperatures, physical and sexual abuse, as well as psychological torture.

In his book, Slahi captured not just the horrors of Guantanamo, but also the humanity.

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"He insists at looking at his own captures - the men and women who he interacts with day to day in Guantanamo - as individuals, thinking about their lives and their choices with a certain level of compassion and empathy and understanding," Larry Siems, the editor of Guantanamo Diary, told Al Jazeera.

Shali's narrative "combats the systematic dehumanisation" of the prison, he added.

In 2010, a federal judge ordered that Slahi be released, ruling "associations alone are not enough" to make his detention lawful.

"The question, upon which the government had the burden of proof, was whether at the time of his capture Slahi was a 'part of' al-Qaida," US District Court Judge James Robertson wrote. "On the record before me, I cannot find that he was."

But the US government appealed, leaving Slahi to linger in his cell, while two other prisoners whose petitions Robertson denied went on to be released from Guantanamo.

It is a "travesty" that six years after he was ordered released Slahi's ordeal has continued, Hina Shamsi, one of Slahi's lawyers and the director of the ACLU's National Security Project, told Al Jazeera. "The PRB is an opportunity finally for [Slahi] to secure his long awaited freedom."

If Slahi's released

If freed, Shali's family will support him and eventually he plans to start a small business and write books. Siems, too, has promised to help with Slahi's future literary works.

One of Slahi's guards in Guantanamo, whom Al Jazeera has identified but is not naming, wrote a letter that was submitted to the review board stating he "would like to eventually see [Slahi] again" and "would be pleased to welcome" the prisoner into his home.

Two other Mauritanians have been imprisoned in Guantanamo. They submitted declarations for Slahi's review hearing describing "positive experiences" upon their return home.

The United States, in its unclassified summary of Slahi, has also expressed concerns about Abu Hafs al-Mauritani, a former senior advisor to al-Qaeda who lives in Mauritania, believing he could provide Slahi "with an avenue to reengage, should he decide to do so".

Mauritania receives security assistance from the US to support its fight against terrorism.

"The Mauritanians have serious security forces and intelligence capabilities and they are completely committed to fighting al-Qaeda-type jihadi violence," said Nasser Weddady, a Mauritanian-American analyst and consultant.

Public opinion in Mauritania is fully in Slahi's corner and over the years this has swayed the government, which has said it would welcome Slahi home. "It is a political liability for the government for [Slahi] not to come back," Weddady added.

A decision by the review board to either clear Slahi for transfer or recommend that he continue to be detained in Guantanamo should be made public in a month's time.

"This is a man with a family, he had a past and he has a future," Siems said. "[He is] not just a man in an orange jumpsuit."

Follow Jenifer Fenton on Twitter: @jeniferfenton