Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. House Democrats Issue Subpoena to White House in Impeachment Inquiry Steve Herman WHITE HOUSE - U.S. Democrats in the House of Representatives have sent a subpoena to the White House for documents related to their impeachment inquiry of President Donald Trump. The heads of three House committees said in a statement Friday that the subpoena is necessary because the White House "refused to engage with -- or even respond to -- multiple requests for documents from our Committees on a voluntary basis." House investigators Friday also sent an extensive request for documents to Vice President Mike Pence about his contacts with Ukraine, citing reports that a Pence aid may have listened to the July phone call between Trump and Ukrainian President Volodymyr Zelenskiy that is at the center of the impeachment investigation. Constitutional duty .