Democratic Sen. Maria Cantwell on Wednesday asked the U.S. Office of Special Counsel to investigate Department of Homeland Security Secretary Kristi Noem for “likely” violating the Hatch Act by making a video to be shown in airports blaming Democrats for the government shutdown.

The Hatch Act bars federal employees, including Cabinet secretaries, from engaging in political activity while acting in their official role.

Multiple major airports have refused to show Noem’s video near passenger screening lines, including Seattle-Tacoma International Airport in Cantwell’s home state of Washington, as well as airports in Chicago and New York.

A number of airports specifically mentioned the video’s potential violation of the Hatch Act in their decision. The Office of Special Counsel is responsible for investigating potential Hatch Act violations.

In a letter to acting Special Counsel Jamieson Greer, Cantwell called out Noem for “airing a partisan video message — on televisions in public airports across the country — in which she erroneously blames ‘Democrats in Congress’ for the current government shutdown’s impact on airport ‘operations’ and for Transportation Security Administration ... employees ‘working without pay.’”