Beijing uses U.S. citizens living in China as a form of leverage. Now lawmakers are pressing Secretary of State Mike Pompeo for more information. “We are deeply concerned by reports that the Chinese government is preventing U.S. citizens from leaving China,” wrote Marco Rubio (R-FL) and Christopher Smith (R-NJ) in a July 17 letter. “This amounts to de facto hostage taking and is unacceptable,” wrote the lawmakers, who chair the Congressional-Executive Commission on China. China uses exit bans to force U.S. citizens, usually of Chinese heritage, to cooperate in investigations or to coerce their relatives in America to return to China. The Daily Beast first reported about the bans in June.