This article was produced in partnership with the Pulitzer Center on Crisis Reporting.

GUANTÁNAMO BAY, Cuba — During the more than three years he spent in C.I.A. prisons before being sent to Guantánamo Bay, Majid Khan says he was hung from his wrists, naked and hooded, for two straight days, causing wild hallucinations.

Mr. Khan, a confessed Qaeda courier, was held in almost total darkness for a year, fearing he would be drowned in an icy tub and isolated in a cell with bugs that bit him until he bled. In 2004, his second year of C.I.A. detention, the agency “infused” a purée of pasta, sauce, nuts, raisins and hummus up Mr. Khan’s rectum when he went on a hunger strike, according to a Senate Intelligence Committee report.

Now Mr. Khan and his legal team are pursuing a strategy in an effort to force the United States government to acknowledge what was done to him in a way it never has for any of the detainees who were subjected to torture — and to give him a measure of compensation for it.

Mr. Khan pleaded guilty at his military tribunal in 2012 to delivering $50,000 of Qaeda money that helped finance the 2003 bombing of a Marriott Hotel in Jakarta, Indonesia, which killed 11 people, and plotting other, unrealized terrorist attacks. He remains in the military prison at Guantánamo Bay, but he has yet to be sentenced because he agreed to become a government witness in return for a chance at leniency.