The ranking Democratic members of the Senate’s Foreign Relations, Banking, and Judiciary committees have written a joint letter to several Trump Administration officials asking them to address the possibility that the Trump Organization violated several laws in its dealings in Azerbaijan. The concerns raised in the letter are based on an article I wrote in The New Yorker about the Trump International Hotel & Tower Baku, a project that was nearly completed but never opened.

The letter, by Senators Sherrod Brown, of Ohio, Dianne Feinstein, of California, and Ben Cardin, of Maryland, was sent to the Attorney General, Jeff Sessions, the Treasury Secretary, Steven Mnuchin, and the F.B.I. director, James Comey. The senators wrote, “It appears that the lack of due diligence by the Trump Organization described in the article exposed President Trump and his organization to notoriously corrupt Azerbaijani oligarchs, and may also have exposed the Trump Organization to the IRGC”—the Iranian Revolutionary Guard Corps. “Even though the Trump Organization appears to have withdrawn from the Baku Tower deal, serious questions remain unanswered about the Trump Organization’s potential criminal liability.”

The article reports that the Trump Organization worked in partnership with companies run by Elton and Anar Mammadov on the Baku luxury hotel and residence, a project overseen by Ivanka Trump. Anar is the son of Ziya Mammadov, who was, until recently, the transportation minister of Azerbaijan. Elton was, at the time of the deal, a member of Azerbaijan’s parliament. The U.S. Foreign Corrupt Practices Act makes it a crime for American companies to provide benefit to foreign government officials in hopes of profiting from their power.

In their letter, the senators asked Sessions and Comey to assess whether the Trump Organization violated the law and whether it acted with “willful blindness,” a legal term referring to a deliberate effort to avoid learning about potentially illicit activity.

The senators also asked Mnuchin to investigate “serious questions about whether the Trump Organization may have become entangled with an IRGC front organization in violation of U.S. sanctions.” As the New Yorker article spells out, U.S. Embassy officials in Azerbaijan have expressed the belief that Ziya Mammadov had an ongoing business relationship with an Iranian construction company, Azarpassillo, which shows many of the hallmarks of being a front for the Revolutionary Guard. The senators asked the Treasury Secretary to work with the director of national intelligence to produce a briefing on the relationship between the Mammadov family and the Revolutionary Guard. The letter also asks for the Treasury’s Office of Foreign Assets Control to open an investigation into “whether or not the Trump Organization violated US sanctions law” by receiving funds from a group linked to the Revolutionary Guard.

The Trump Organization did not respond to a request for comment about this letter. However, its chief legal officer, Alan Garten, told The New Yorker earlier, “We had no equity. We didn’t control the project. The flow of funds is in the wrong direction. We did not pay any money to anyone. Therefore, it could not be a violation of the F.C.P.A.” At time of publication, representatives for the Republican committee chairs had yet to respond to the call for an investigation.