Democrats pushed back against the Republican effort to vilify Mr. Bragg while laboring to show sympathy for the victims.
“I fear that you are being used for a political purpose, despite your sincerity,” said Representative Zoe Lofgren, Democrat of California, prompting objections from the witnesses.
The hearing came a week after Mr. Bragg filed a lawsuit against Mr. Jordan seeking to stop congressional Republicans from interfering in his case against Mr. Trump — the product of a nearly five-year investigation that began under his predecessor — and specifically, to bar them from deposing Mark F. Pomerantz, a lawyer who worked on the inquiry for about a year.
On Monday, as the congressional hearing was getting underway, a lawyer for Mr. Jordan filed a response to Mr. Bragg’s lawsuit, saying that it represented “an extraordinary and unconstitutional” attempt to have a judge interfere in a congressional inquiry.
A lawyer for Mr. Bragg declined to comment on Mr. Jordan’s response.
The hearing was repeatedly interrupted by protesters and outbursts. At one point, a group loudly attempted entry into the hearing room, chanting, “Let us in!” They held signs that said “Jim Jordan, Insurrectionist,” referring to the Ohio Republican’s role in planning the efforts in Congress on Jan. 6, 2021, to overturn the election results, and “34 felonies,” a reference to the charges against Mr. Trump.
Antisemitism was on vivid display. Outside the Javits building, a man held a sign with the name of the financier George Soros, a Jewish Holocaust survivor, along with the image of a Star of David and dollar signs. Several Republicans inside the hearing room also focused their comments on Mr. Soros, whom they blamed for supporting the campaigns of progressive prosecutors, including Mr. Bragg’s.
“With antisemitic tropes emanating from House Republicans, it’s unsurprising, but no less vile, to see the Republicans bringing this antisemitism to New York outside today’s stunt hearing in Manhattan,” said Representative Jerrold Nadler of New York, the top Democrat on the committee.