Chaudhry has served legal notice to the U.S. authorities and will sue if they do not respond within a month. He said that he believed his client’s mental health had been affected during his captivity.
"Sometime I did feel that he was a little mentally deranged and disturbed, of course … there was an incoherence in his speech when he was telling me details of all those events he went through," he told the British broadcast.
The legal notice says Sagheer suffered "mental shock, financial loss, physical victimization, estrangement and religious victimization."
Sagheer says he underwent periods of solitary confinement during his captivity and was served alcohol-laced drinks – contrary to his religion of Islam.
He says he witnessed scores of people dying including 50 who suffocated to death as he was transported across Afghanistan.
Sagheer was on a preaching mission in northern Afghanistan when he was arrested by Afghan warlord General Rashid Dostum and handed to the U.S. authorities.
On being handed to the American authorities, he says he was deprived of food, forbidden to pray and made to shave off his beard.
Sagheer also says he saw hundreds of fellow prisoners die in U.S. bombardments of northern Afghanistan.
Asked about the impact of captivity on Sagheer, the lawyer told the BBC: "He seems to be normal but the conditions he went through have definitely had a very deep impact on his health and on his condition as a whole.
Another Pakistani released from the notorious camp in Cuba said in May 2003 that most of the 600-plus prisoners still held there on suspicion of Al-Qaeda links had become mentally disturbed.
Two others of the freed men, a Pakistani and an Afghan, told The New York Times last month about the overwhelming feeling of injustice among the inmates detained indefinitely at the U.S. naval base.