Impeachment Inquiry Witness Asks Court To Weigh In On Congressional Subpoena : The NPR Politics Podcast Investigators in the impeachment inquiry of President Trump hoped to talk to Charles Kupperman on Monday. But the former White House official failed to show up. This episode: White House correspondent Tamara Keith, White House correspondent Franco Ordoñez, and national political correspondent Mara Liasson. Email the show at firstname.lastname@example.org. Find and support your local public radio station at npr.org/stations.