Acting Ambassador William Taylor is escorted by U.S. Capitol Police on Tuesday as he arrives to testify before House committees as part of the Democrats' impeachment inquiry into President Trump.
J. Scott Applewhite/AP
Then-U.S. special envoy for Ukraine Kurt Volker speaks during a news conference in Kyiv on July 27. Volker is being deposed on Thursday as part of the House impeachment inquiry.
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