Updated

A former inspector general for the Defense Department is calling on Congress to investigate and oversee the vetting process for Muslim clerics who are nominated to serve as U.S. military chaplains.

In a letter sent earlier this month to Sen. Dianne Feinstein, chairwoman of the Senate Intelligence Committee, former Inspector General Joseph Schmitz outlined what he believes is the potential risk to national security posed by the military’s current chaplain vetting system.

Among the concerns Schmitz outlined in his letter, which was obtained by FoxNews.com, are:

— Reports that Army Maj. Nidal Hasan, accused of 13 counts of murder in last year's Fort Hood massacre, acted as a Muslim lay leader and received training from one of the approved civilian religious groups involved with the Defense Department chaplain program.

— The identification of the Islamic Society of North America (ISNA), one of two endorsing agencies used by the U.S. military in its approval process for Muslim chaplains,as an unindicted co-conspirator in the 2008 Holy Land Foundation terror fundraising trial.

— The naming of the ISNA's former endorsing agent, Dr. Louay Safi, as an unindicted co-conspirator in the 2003 trial of Sami Al-Arian, who pleaded guilty to one count of fundraising for the terrorist organization Palestinian Islamic Jihad. Safi is also the subject of a whistleblower investigation.

“The November 2008 criminal conviction in Texas of the Holy Land Foundation (HLF) as a front for Hamas, naming of the DoD's Chaplain Endorsing Agents, the Islamic Society of North America (ISNA), as an unindicted co-conspirator (among others), suggests that terrorist organizations can and do disguise themselves as charitable organizations," Schmitz wrote to Feinstein.

"The November 2009 Fort Hood massacre by a commissioned Army officer who served as a lay Muslim leader at Fort Hood demonstrates that international terrorist organizations can also try to disguise their agents as chaplains and religious lay leaders," he added.

In a statement to FoxNews.com, Feinstein, D-Calif., said:

“We recently received the letter and staff is reviewing it carefully and making inquiries into how all chaplains are vetted by the Defense Department. Certainly chaplains should be carefully interviewed and backgrounds checked, regardless of their religion.”

Prospective military chaplains currently are recommended to the U.S. military by outside religious organizations, which in turn select an endorsing agent who is charged with issuing and withdrawing the chaplains' credentials for the Defense Department. Candidates undergo the same fingerprinting and background check required of members of the military, but Schmitz maintains this is not an adequate screening.

Schmitz says he made a series of recommendations for vetting chaplain nominees six years ago that were not implemented by the Defense Department. In his Nov. 8 letter to Feinstein, he wrote that he had recommended that nonreligious criteria be established to justify the withdrawal or removal of a religious organization or its agent from participating in the DoD chaplain program. Examples of such criteria could include:

— Advocating the violent overthrow of the U.S. government;

— Being listed on a watch list as a terrorist organization;

— Conviction of a religious organization or its principal leaders in connection with terrorism;

— Conviction of endorsing agents in connection with any criminal activity.

He said he also recommended developing screening procedures for collecting information from sources, including  FBI databases relating to chaplains, supporting religious organizations and endorsers.

But Schmitz says his recommendations were shot down by the Armed Forces Chaplains Board, which called those suggestions “legally problematic." His account is confirmed by the department response to the 2004 report.

Defense Department spokeswoman Eileen Lainez told FoxNews.com that some of Schmitz's recommendations have since been incorporated into vetting policy.

Now, Lainez said, any individual or religious organization shall be rejected or removed from participation in the DoD chaplain program if they're under indictment; have been convicted of a terrorism-related offense or other offense threatening national or economic security; or if their name appears on the annual State Department list of Foreign Terror Organizations.

"In addition, following the release of the Fort Hood report, this policy has been under review to see if there are other additional criteria that can be included," Lainez said.

In his letter, Schmitz asked Feinsten to ask the Defense Department to take another look at his earlier, non-implemented recommendations.

Citing reports that Hasan acted as a lay leader, a sort of substitute or part-time chaplain required to undergo a vetting process similar to those of full-time chaplains, he wrote in an email to FoxNews.com:

“Somebody ought to challenge the DoD on precisely how it vets its chaplains as well as its chaplain ‘endorsing agents’ to ensure non-complicity in terrorism or criminal activities, and who, if anyone, vetted Major Nidal Hasan as a so-called ‘Muslim lay leader’ at Fort Hood.”

In his letter to Feinstein, he also argued that the 2008 Holy Land Foundation terror fundraising trial in itself should be enough to reconsider the organizations currently tasked with endorsing chaplain candidates. During that trial, prosecutors named the ISNA, among other well-known Muslim organizations, as an unindicted co-conspirator in the case that convicted a Texas charity of acting as a front for Hamas. (A court document unsealed two weeks ago reaffirms the prosecution’s stance that ISNA, among other groups, was tied to HLF's fundraising for Hamas.)

Yet, ISNA remains one of two ecclesiastical endorsing agencies used to vet Muslim chaplain candidates for the military.

ISNA did not reply to requests for comment.

Schmitz also specifically named ISNA’s chaplain endorsing agent, Dr. Louay Safi, who acted on behalf of ISNA and until recently was one of two Defense Department Muslim chaplain endorsing agents for the entire U.S. military.

Safi, who has participated in Pentagon programs since at least 2005, was named as an unindicted co-conspirator in the 2006 Al-Arian case. (During the trial, Safi was identified as "Unindicted Co-Conspirator Four," and evidence from the case included wiretapped phone conversations between him and Al-Arian.)

Safi is also the subject of a whistleblower complaint filed late last year by a contractor who expressed concern with Safi's participation in a lecture on Islam to soldiers at Fort Hood before their deployments in the weeks after the deadly shooting there.

Safi was suspended from participating in military lectures pending the outcome of the whistleblower investigation, according to email records that were obtained by FoxNews.com. But he continued to act as one of two Muslim chaplain endorsing agents working with the Defense Department.

Until a week and a half ago, Safi’s name appeared on the DoD’s website listing of ecclesiastical endorsing agents. But on Nov. 18, a spokeswoman for the Defense Department said Safi was no longer an endorsing agent, and that a request had been submitted to change the website back in June. Safi's name was removed from the site later that evening.

When reached by phone, Safi told FoxNews.com:

"I left ISNA, I am now with another institution. I moved on to another career."

He also said that he was unaware of any whistleblower complaint or investigation.

"That's probably something you read on some blog that is not true," he said. "There was nothing — not that I'm aware of."

The status of the investigation into the whistleblower complaint about Safi is unclear. A spokesman for the Naval Criminal Investigative Service said the case was handed off to the Army, and an Army spokesman said the Army never opened a case because Safi is a civilian.

Walid Phares, director of the Future of Terrorism Project at the Foundation for Defense of Democracies, echoed Schmitz’s concerns, calling ISNA’s involvement in the military chaplain program a matter of urgent national security.

“The main concern is that the body consulted by the U.S. government to select the chaplains is made of NGOs linked to the Jihadists or to Islamist movements. This alone compromises national security,” he said.

“It would be placing — without knowledge — religious advisers to military personnel who promote Islamist ideologies and doctrines. This would be the single most dangerous penetration self inflicted by the bureaucracy.”