Sparring in Trump Documents Hearing Highlights Case’s Slow Pace

The judge handling former President Donald J. Trump’s classified documents case in Florida got into a heated exchange with a federal prosecutor on Wednesday over a minor but bitterly contested issue, highlighting again how bogged down the proceedings have become.

In this case, the topic was an unproven accusation by Mr. Trump’s legal team that at an early stage of the inquiry prosecutors sought to get one of his co-defendants to cooperate against him by threatening his lawyer.

The exchange occurred at a hearing where the prosecutor, David Harbach, angrily denied the accusation and the judge, Aileen M. Cannon, pressed him for details. The dispute concerned a meeting nearly two years ago at the Justice Department. A lawyer for the co-defendant, Walt Nauta, claims that prosecutors hinted that they could derail a judgeship he was seeking if he did not prevail on Mr. Nauta to turn on Mr. Trump.

“The story about what happened at that meeting is a fantasy,” Mr. Harbach told Judge Cannon at one point. “It did not happen.”

The testy conversation ended with Judge Cannon advising Mr. Harbach to calm down. It was emblematic of the mounting frustration that prosecutors in the office of the special counsel, Jack Smith, have evinced not only toward defense lawyers in the case, but also toward the judge herself.

The dispute came on the heels of Mr. Trump’s legal team making several aggressive — and some unfounded — allegations of prosecutorial misconduct and political gamesmanship against Mr. Smith in a pair of motions unsealed on Tuesday.