Some of the Republicans brought their cellphones into the secure room, which is not permitted and considered a security breach. The sergeant-at-arms, the top law enforcement officer in the Capitol, was called in to handle the situation as Representative Adam B. Schiff, Democrat of California and the chairman of the House Intelligence Committee, attempted to intervene.
The standoff stretched into the afternoon as protesting Republicans ordered pizza and fast food for the throng of reporters assembled to witness their spectacle. It came the day after the explosive testimony of William B. Taylor Jr., the top American diplomat in Ukraine, who effectively confirmed Democrats’ main accusation against Mr. Trump: that the president withheld military aid from Ukraine in a quid pro quo effort to pressure that country’s leader to incriminate former Vice President Joseph R. Biden Jr. and smear other Democrats.
Democrats said the timing was no coincidence, and characterized the Republican disruption — “sit-in, stand-in, call it whatever you want,” said Representative Harley Rouda, Democrat of California — as a desperate attempt to deflect attention from the damaging testimony.
At the White House, Mr. Trump took to Twitter to assail Mr. Taylor and his lawyer John Bellinger — and to offer encouragement to Republican protesters.
“Never Trumper Republican John Bellinger, represents Never Trumper Diplomat Bill Taylor (who I don’t know), in testimony before Congress!” the president wrote. “Do Nothing Democrats allow Republicans Zero Representation, Zero due process, and Zero Transparency.”
For weeks now, lawmakers on three House committees — Intelligence, Oversight and Reform, and Foreign Affairs — have been conducting private question-and-answer sessions, which have produced a stream of compelling testimony from government witnesses, much of it confirming and expanding on the intelligence whistle-blower complaint that touched off the impeachment inquiry.
Those sessions are attended by both Democrats and Republicans, and both have an opportunity to question witnesses; more than 100 of the 435 members of the House are eligible to participate. Democrats have said that they plan to hold open hearings after the committees finish deposing witnesses, and that they intend to make public complete transcripts of witness testimony after they have been reviewed for classified material.