WASHINGTON — Two minutes into Monday’s historic House Judiciary Committee hearing into the impeachment of President Trump — even before Representative Jerrold Nadler, the chairman, issued the customary call for decorum — a protester, screaming that Mr. Nadler was committing treason, was dragged out of the grand columned hearing room by the Capitol Police.
It was the first clue that this was not going to be a somber session befitting the gravity of the occasion.
The hearing was intended as an opportunity for Democrats to lay out their case that Mr. Trump had violated the Constitution with a “brazen” scheme to enlist Ukraine to interfere in the 2020 election — and for Republicans to respond. But it quickly devolved from a staid courtroom drama into a raucous, gavel-banging, partisan verbal melee.
“You will not shout out — not shout out in the middle of testimony,” a frustrated Mr. Nadler exclaimed at one point, bringing the gavel down in a fruitless effort to shut down Republican parliamentary objections.
“Bang it harder — it still doesn’t make the point that you’re not doing it right,” Representative Doug Collins, the top Republican on the Judiciary Committee, shot back.
Republicans brought big props, including two giant poster boards assailing Representative Adam B. Schiff, Democrat of California and the chairman of the Intelligence Committee, who led the fact-finding portion of the impeachment inquiry and has turned down Republican calls to testify about his work. “Where’s Adam?” one placard blared, in simple black and white. Another featured a red and white milk carton with Mr. Schiff’s picture under the word “MISSING.”
Democrats brought big-name lawyers from New York: Daniel S. Goldman, a former federal prosecutor and MSNBC legal analyst who is the chief investigator for the Intelligence panel and Barry H. Berke, a white-collar defense lawyer known as a relentless interrogator, currently working for the Judiciary. Mr. Berke wore two hats: After testifying alongside the Republicans’ lawyer, Stephen R. Castor, he questioned Mr. Goldman and Mr. Castor, rattling the Republican with his rat-a-tat style.
“Come on, Barry,” Mr. Castor complained at one point, his face scrunching in frustration.
From the start, Mr. Castor, a veteran congressional investigator whose off-duty passions include the Grateful Dead and the Philadelphia Phillies, gave off a workaday vibe. He brought his briefing papers in a reusable grocery bag from Fresh Market, prompting the food chain to seize on a marketing opportunity.
“We’d like to announce that we are the official briefcase maker of Steve Castor,” the chain wrote on Twitter, with a winking, tongue-wagging emoji and an offer of free bags.
It all unfolded on a split-screen day in Washington, with the scene in the hearing room countered by the release of a long-awaited report by the Justice Department’s inspector general that debunked President Trump’s accusations that former leaders of the F.B.I. engaged in a politicized conspiracy to sabotage him.
Hovering over the proceedings — unseen but very much heard — was the president, who had refused Democrats’ entreaties to participate in the hearing. He made an appearance of sorts, thanks to Mr. Nadler’s team, which showed him on videotape declaring “I have an Article 2 where I have the right to do whatever I want as president,” a clear indication, Democrats argued that the president thinks he is above the law.
And Mr. Trump could not stay away on Twitter. “Witch Hunt!” he wrote in his first missive of the day, followed quickly by “The Do Nothing Democrats are a disgrace!”
To those who remember the somber Watergate hearings of 1974, or even the more partisan 1998 hearing featuring Ken Starr, the independent counsel whose investigation led to the impeachment of President Bill Clinton, Monday’s hearing was still striking in its rancor — so much so that Robert Dallek, the presidential historian, thought it might come to fisticuffs.
“It’s so unpleasant, nasty, out of sync with traditional American politics,” Mr. Dallek said. “Not because politics is a soft business or an easy business, but there are degrees and degrees. Frankly, as I watched some of this stuff, it seemed to me like it could become almost physically violent.”
The session opened shortly after 9 a.m., with the bespectacled Mr. Nadler, who spent the weekend in mock hearings with his Democratic colleagues and staff, presiding. Mr. Nadler was a few sentences into his opening statement when Owen Shroyer, a host on the website Infowars, which traffics in conspiracy theories, jumped out of his seat, hollering about treason and an “impeachment scam.” The Capitol Police rushed in to escort him out.
For a couple of hours after that, the session was relatively calm — albeit a recitation of alternate versions of reality.
Mr. Berke laid out the case for impeaching Mr. Trump, as Democrats saw it. Mr. Castor said there were no grounds.
Mr. Goldman, a former mob prosecutor, repeatedly used the word “scheme” as he unspooled the by now well-known narrative of Mr. Trump’s pressure campaign in Ukraine — including the July 25 call in which Mr. Trump asked President Volodymyr Zelensky of Ukraine to “do us a favor” and investigate former Vice President Joseph R. Biden Jr. and his son.
Mr. Castor portrayed the call as one of “pleasantries and cordialities,” adding, “Simply put, the call is not the sinister mob shakedown that some Democrats have described.”
But things took a turn for the explosive once the questioning began. As Mr. Berke grilled Mr. Castor, Republicans cried foul.
“Is this when we just hear staff ask questions of other staff and the members get dealt out of this whole hearing?” Representative Matt Gaetz, Republican of Florida, and one of Mr. Trump’s most ardent defenders on Capitol Hill.
“The gentleman will suspend!” Mr. Nadler declared, with another bang of the gavel, using a slightly politer congressional euphemism for silencing an interruption.
When Mr. Berke was done questioning, Mr. Collins stepped in for the Republicans to hammer away at Mr. Goldman. “Answer the question!” he said sharply, as Mr. Goldman paused before responding. “Mr. Berke had so much free rein — let’s go at it.”
In a sense, said Mr. Dallek, the historian, the session was a reflection of the president himself: partisan, combative, not willing to give an inch. In his opening statement, Mr. Berke offered insight into the mind-set of Democrats as he recounted an anecdote involving his young son.
“He said ‘Dad, does the president have to be a good person?’” the lawyer said, before offering his own answer: “I said, ‘Son, it is not a requirement that the president be a good person, but that is the hope.’ ”