The American Civil Liberties Union (ACLU) issued writs against two psychologists who devised the CIA's Bush-era interrogation programme on Tuesday (13 October), saying they encouraged the agency "to adopt torture as official policy".

James Mitchell and Bruce Jessen, two former military psychologists, "designed the torture methods and performed illegal human experimentation on CIA prisoners to test and refine the programme," the ACLU said in a statement. "They personally took part in torture sessions and oversaw the programme's implementation for the CIA," it added. ACLU also said the men enriched themselves to the tune of millions of dollars in the process.

The lawsuit was filed in federal court in Washington state on behalf of three US prisoners: Gul Rahman, Suleiman Abdullah Salim and Mohamed Ahmed Ben Soud. "There's been no accountability for these men. They've received no apologies. They've received no compensation and Gul Rahman's family has never even received his body," Dror Ladin, an ACLU attorney, said. Gul died from hypothermia caused by dehydration and hypothermia, while the other two are said to have suffered lasting psychological and physical damage.

"Now that the Senate torture report that came out at the end of last year provided enormous details about Mitchell and Jessen's role in the torture programme, now is the time that our clients thought was right to try to seek justice and accountability," Ladin said.

A US Senate report last year found the CIA paid $80m (£52m) to a company run by two former US Air Force psychologists with no experience in interrogation or counterterrorism who recommended waterboarding, slaps to the face and mock burial for prisoners suspected of involvement in terrorism. The two were not named in the report but intelligence sources later identified them as Mitchell and Jessen.

According to Ladin, their methods were extensive. "Hanging people up in very painful stress positions for days on end so they couldn't sleep; they involved waterboarding; they involved dousing people with water; they involved stuffing people into small boxes that were smaller than coffins for extended periods," he said. "[They would] keep people naked with very little food in freezing-cold rooms and total darkness; bombard them with very, very loud music or sounds – it was an effort to really break people down."

The US never charged the men with a crime. The lawsuit said the psychologists were liable for war crimes including torture and non-consensual medical and scientific human experimentation. According to Ladin, Mitchell and Jessen were likely not totally surprised by the ACLU filing.

"I can only speculate that Mitchell and Jessen may have figured that one day their victims would sue them, because the contract that they entered into with the CIA included a $5m legal indemnity for them and for their corporation that was involved in the torture. We're glad that our clients are having their moment now," he said.

The CIA outsourced more than 80% of its interrogation programme to the company, Mitchell Jessen & Associates of Spokane, Washington, for its work from 2005 until the termination of the arrangement in 2009, the senate report said. The CIA also paid the company $1m to protect it and its employees from legal liability. The lawsuit seeks unspecified damages of a minimum $75,000 for the men. The CIA declined to comment on the suit.