Three Minnesota state lawmakers, including House Speaker Kurt Daudt, spent nine days in Turkey at the end of last month at the invitation of a U.S. nonprofit with ties to a controversial Turkish religious figure.

Republicans Daudt of Crown and Rep. Ron Kresha of Little Falls, along with DFL Rep. Paul Rosenthal of Edina, traveled to Turkey from Nov. 20 to 29 with a delegation from the Chicago-based Niagara Foundation. The organization was founded by followers of Fethullah Gulen, the leader of a Turkish religious movement who has lived in self-imposed exile in the U.S. for two decades.

The 74-year-old Gulen is a former imam known for a progressive approach to Islam, having advocated dialogue between Muslims and other faith groups, openness to agnosticism and atheism, and for women’s rights, education and a modern economy. A former ally to current Turkish President Recep Tayyip Erdogan, their relationship has soured in recent years.

In October, Agence France-Presse reported based on local media reports that Gulen would go on trial in absentia this January on terrorism charges for allegations he conspired to bring down Erdogan. Gulen has denied the allegations. When President Obama visited Turkey last month, Erdogan reiterated a previous request that the U.S. extradite Gulen back to Turkey.

“I was not aware of the issue you raised when I signed up to participate,” Rosenthal said in an e-mail inquiring about the trip.

Rosenthal and Kresha responded to inquiries about the trip via e-mail, and Daudt through a spokeswoman. Daudt and Kresha also said they didn’t know about controversy surrounding Gulen before the trip.

“Understanding the earliest days of western civilization is a passion I possess,” Kresha wrote. “Seeing the caves of Cappadocia where early Christians hid, the ruins of Ephesus where St. Paul preached, and the Palace of the Ottoman Empire furthered my historical perspective.”

Spokespeople for all three lawmakers stressed that no taxpayer dollars went to the trip. The Niagara Foundation’s invitation to Minnesota lawmakers said participants would pay their own airfare and a $750 fee; lodging and travel costs while in the country were to be paid by the organization. That’s perfectly legal. Minnesota’s “legislative gift ban” prohibits state lawmakers from accepting gifts from registered lobbyists or lobby groups. The Niagara Foundation does not fit that criteria.

The group has funded numerous trips for U.S. politicians and academics, according to foundation spokesman Josh Heine. Gulen himself is the “honorary president” of the Niagara Foundation, but Heine said he has no functional role in the organization.

A USA Today investigation published in October found that a dozen different groups associated with Gulen’s movement had funded some 200 trips to Turkey for members of Congress and their staff since 2008, possibly in violation of House rules and federal law.

Six Minnesota lawmakers previously went on a similar trip to Turkey.