The Republicans have refrained during hearings from explicitly accusing the individual of filing the explosive complaint with the U.S. intelligence community’s inspector general two months ago, officials said.

But the questions have been interpreted as an attempt “to unmask the whistleblower,” whose identity is shielded under federal law, said a person with direct knowledge of the depositions. Republicans appear to be seeking ways to discredit the whistleblower as well as other witnesses “by trying to dredge up any information they can,” the official said…

Republicans have also asked witnesses to affirm that the president has publicly stated there was no quid pro quo, officials said, and that it is appropriate for the U.S. government to withhold aid from foreign governments deemed to be corrupt.

Republicans have also used their time to go after Biden, including citing Trump’s unsubstantiated allegation that Biden used his position as vice president to pressure Ukraine to fire a prosecutor who had been investigating the energy company that had employed Biden’s son Hunter. During an interview with George Kent, the deputy assistant secretary of state responsible for Ukraine, GOP questioners repeatedly asked the diplomat whether the United States had led the effort to remove the Ukrainian prosecutor, Viktor Shokin.