And Iran's quasi-official Fars News Agency over the weekend called him "among the most vocal advocates of the terrorist [MEK]," which Iran blames - with Israel - for deadly attacks on its nuclear scientists.
In Paris on Feb. 11, Rendell said the plight of MEK members in Iraq was "a humanitarian cause and it was necessary for all of us, my country, the world community, the United Nations, to stand up and do the right thing." He also effusively praised the group's leader, Maryam Rajavi, and proclaimed, "I love coming to Paris."
Contacted on Sunday and Monday by The Inquirer, Rendell hung up the phone twice with a "no comment."
But in a lengthy voice message left later Monday, he spoke of 46 people, including eight women, who were killed in attacks by Iraq's current regime in 2009 and 2011.
"I feel passionate that nothing happens to those people," he said.
He declined to discuss the Treasury inquiry. "I'm sorry, I can't comment," he said, "because of the subpoena," first reported by the Washington Times on Friday. It was sent to William Morris Endeavor Entertainment, which handles Rendell's speaking engagements.
In MEK's early history, the group was involved in attacks on Americans in Iran in the 1970s. During the Iran-Iraq War in the 1980s, exiled MEK forces fought with former Iraqi leader Saddam Hussein against the government in Tehran.
Hussein rewarded the group with an outpost in Iraq 25 years ago, Camp Ashraf, north of Baghdad, where about 2,800 members are currently holed up.
Today, the Iraqi government wants the MEK contingent at Camp Ashraf to leave, and that has led to the bloody clashes. MEK has renounced violence. Under an agreement negotiated with the United Nations, the group must move to another former American base - Camp Liberty - near the Baghdad airport, until they can be resettled outside Iraq.
Rendell suggested that The Inquirer reach out to former Gov. Tom Ridge, who also was the first secretary of Homeland Security. "Gov. Ridge was active in this even before I got involved," Rendell said in his message.
Several calls to Ridge's Washington consulting office were not returned.
Besides Rendell and Ridge, the MEK issue has attracted a bipartisan A-list of Washington lawmakers, former cabinet officials and retired generals who are calling for two things: help for MEK members at Camp Ashraf in Iraq and removal of the organization from the terrorist list.
Among the high-profile supporters are former New York Mayor Rudolph Giuliani; former FBI Director Louis Freeh; former Vermont Gov. Howard Dean; former National Security Adviser Gen. James Jones; former White House chief of staff Andy Card; retired Gen. Wesley Clark; former Sens. Robert Torricelli of New Jersey and Evan Bayh of Indiana; former CIA Director Porter Goss; and former Joint Chiefs Chairman Gen. Richard Myers.
"I got involved because they asked me," Rendell said in his voice message. "I did extensive research and I looked at the other people who were involved and they were generals and former elected officials."
"I had great confidence in them," he said.
Rendell likened his support of MEK to his endorsement of President Obama's decision to back NATO intervention in Libya, saving opposition forces in Benghazi.
"The U.S. in 2003 signed an agreement with MEK to disarm and in return . . . the U.S. would protect them," Rendell said. "And yet we didn't fulfill our obligation and the Iraqi government twice attacked Ashraf where no one had arms."
A network of MEK support groups has paid VIP supporters to lobby for its delisting from the terrorist list.
On another front, MEK is trying to get the courts to set a deadline for the State Department to make a decision on whether to take it off the terrorist list.
"The Department of State is still reviewing MEK's designation," said Laura Seal, a spokeswoman at State.
Meanwhile, the drumbeat of support from advocates continues. Ridge wrote in a Jan. 26 column for Fox News that "unshackling the MEK from an unjust blacklist" would send the "mullahs' terrorist regime in Tehran exactly the message it needs to hear."
Rendell made his first address in support of MEK last July 16 at a conference on MEK in Washington. His most recent appearance was on Feb. 11 at a conference in Paris, attended by thousands of Iranian exiles.
In his message, Rendell did not say how much money he has been paid to advocate for MEK.
Titra Parsi, founder of the National Iranian American Council and author of A Single Roll of the Dice: Obama's Diplomacy With Iran, said the federal government was long overdue in questioning people paid to express their support of MEK.
He said some former officials had received $25,000 for expressing support for the exiles at Camp Ashraf and double that amount if they advocate for taking MEK off the terrorist list.
Parsi said MEK remains on the terrorist list and until it is removed, Americans cannot be paid to support it.
He said the subpoena for information from Rendell may be an attempt by Treasury to see whether payments for speeches were directly or indirectly tied to MEK.
"You have to be extremely careful if you have anything to do with anyone on the terrorist list," added Jerry S. Goldman, a New York attorney representing a plaintiff in a lawsuit against the Saudi Arabian government and its alleged involvement in financing 9/11 attackers.
"The current definition of providing support [to a terrorist group] is extraordinarily broad," Goldman said.
Contact Jennifer Lin
at 215-854-5659, firstname.lastname@example.org.,
or j_linq on Twitter.