The White House is facing tough questions over its firing of a longtime railroad official, with some alleging that a murky process led to the dismissal and requires reform.

Martin Dickman, who had served as the U.S. Railroad Retirement Board inspector general since 1994, was let go in March on grounds of creating a hostile work environment. But Sen. Chuck Grassley (R-IA) says the reasons he was let go have not been made clear by the Biden administration.