A bipartisan pair of lawmakers sent letters on Thursday to 18 federal agencies requesting information about their compliance with the Hatch Act, a law designed to create a firewall between political activities and official duties for members of the administration.

The letters came just days after a complaint against Housing and Urban Development Secretary Julian Castro was made public. That complaint, investigated by the Office of Special Counsel, discovered Castro had violated the Hatch Act by commenting on the presidential race during an interview dedicated to promoting HUD policies.