WASHINGTON (RNS) Twenty religious organizations are calling for Congress and President Obama to ensure a fair and thorough investigation into allegations of forced human experimentation by the CIA on detainees after 9/11.

In June, the group Physicians for Human Rights (PHR) released “Experiments in Torture” which detailed health professionals’ involvement in CIA interrogation programs.

The report alleged that the CIA used forced human experimentation for several purposes, including calibrating “the level of pain experienced … ostensibly to keep it from crossing the administration’s legal threshold of what it claimed constituted torture.”

Religious groups affiliated with the Washington-based National Religious Campaign Against Torture (NRCAT) and the doctors groups are now asking government leaders to consider the findings and take steps to ensure the practice is discontinued.

Ranging from the Hindu American Foundation and Islamic Society of North America to Rabbis for Human Rights-North America and the Quakers, the religious groups say investigations into the allegations have been mishandled or ignored.

The Office of Human Research Protection in the Department of Health and Human Services declined to investigate the allegations, instead referring the complaint directly to the CIA.

“If OHRP receives an allegation … related to human subjects research that is conducted or supported by a federal department or agency other than HHS, OHRP will refer the matter to the other department or agency for review and action as appropriate,” Assistant HHS Secretary Howard Koh wrote in a July 1 letter.

Since the alleged research infractions “appear to be subject to the oversight of the CIA,” HHS forwarded the complaint “to the CIA for review.”

The religious groups are skeptical, however, at the CIA’s ability to investigate itself.

“The CIA has already publicly denied these allegations and declined to investigate,” said the Rev. Richard L. Killmer, executive director of NRCAT, in a statement. “So it makes no sense to refer the complaint to them alone.”

In addition to the 20 religious groups, some 3,000 individuals have also signed on as complainants.

“The evidence is absolutely shocking and repulsive,” said the Rev. Michael Kinnamon, general secretary of the National Council of Churches. “Torture is an affront to God and the denial of the bedrock convictions of all people of faith.”