The chairman of the Ways and Means Committee filed a brief in federal court saying the plea agreement for the president’s son had been tainted by political interference.
Republicans are raising fresh concerns about CATL, the battery maker Ford is working with to bring new technology to the U.S., and its connections to Xinjiang.
The demand for interviews with more than a dozen federal officials comes as the G.O.P. hunts for evidence that the government improperly protected the president’s son from felony prosecution.
A whistle-blower said the tax agency found a message from 2017 in which Hunter Biden pressured a Chinese business partner by saying he was with his father, who was then out of office.