U.S. House of Representatives committees conducting an impeachment inquiry of President Donald Trump said on Tuesday they had asked Mick Mulvaney, the acting White House Chief of Staff, to appear for a deposition on Nov. 8. 'Based on evidence gathered in the impeachment inquiry and public reporting, we believe that you possess substantial first-hand knowledge and information relevant to the House's impeachment inquiry,' leaders of the House Foreign Affairs, Intelligence and Oversight committees said in a letter to Mulvaney.