Empower Oversight, a group of lawyers including former aides to Senator Charles E. Grassley, Republican of Iowa, is part of a constellation of groups facilitating G.O.P. investigations in Congress.
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.
An I.R.S. investigator’s testimony describing strains over the inquiry into President Biden’s son is at odds with the version laid out by Attorney General Merrick Garland.