The top U.S. psychology association has apologized for the group's collusion with the U.S. Defense Department and the CIA to issue guidelines that supported torture, including waterboarding and sleep deprivation, following the September 11 terrorist attacks on the country 14 years ago.

"We profoundly regret and apologize for the behavior and the consequences that ensued," said Dr. Nadine Kaslow, who led the committee that commissioned a report on the allegations.

The American Psychological Association (APA) retained attorney David Hoffman to conduct an independent review that resulted in a 542-page report detailing the relationship between various activities of the APA and the Bush Administration policies on interrogation techniques.

The Hoffman report said the intent of the people who participated in the collusion was to "curry favor" with the Defense Department, possibly enabling the government's use of abusive interrogation techniques.

'Unethical behavior'

The report found the ethical guidelines "prioritized the protection of psychologists -- even those who might have engaged in unethical behavior -- above the protection of the public."

The review also found that two former APA presidents sat on CIA advisory committees.

One told the agency he did not think sleep deprivation constituted torture.

The report "contains deeply disturbing findings that reveal previously unknown and troubling instances of collusion," said Dr. Susan McDaniel, a member of the APA's Independent Review's Special Committee.

"The actions, policies and the lack of independence from government influence described in the Hoffman report represented a failure to live up to our core values, Kaslow said.

"Our members, our profession and our organization expected and deserved better," she said.