A federal judge in Florida stopped the Justice Department on Tuesday from releasing to Congress a potentially damning section of a report by the former special counsel, Jack Smith, detailing his lengthy investigation of President Trump’s mishandling of classified documents.

In a strongly worded 14-page order, the judge, Aileen M. Cannon, said that federal prosecutors should not be allowed to share the section of the two-volume report with anyone outside the Justice Department, including members of Congress, given the risk that the information, some of which she said had not yet been made public, could slip out.

“Given the very strong public interest in this criminal proceeding and the absence of any enforceable limits on the proposed disclosure, there is certainly a reasonable likelihood that review by members of Congress as proposed will result in public dissemination of all or part” of the report, she wrote.

Before Mr. Trump took office and assumed control of the Justice Department, Merrick B. Garland, then the attorney general, had proposed showing the classified documents section of Mr. Smith’s report to the four top leaders of the House and Senate Judiciary Committees.

While Mr. Garland released the other volume of Mr. Smith’s report — which concerned a separate criminal case that accused Mr. Trump of plotting to overturn the 2020 election — to the public, he was reluctant to take similar steps with the volume on classified documents.

That was because the documents case is still active against Mr. Trump’s two-co-defendants, Walt Nauta and Carlos De Oliveira, and Mr. Garland was sensitive about revealing any information that could affect pending legal proceedings involving them.

At a hearing last week about what to do with the documents volume of the report, Judge Cannon asked why the Justice Department under Mr. Garland had wanted to move quickly in giving that section to lawmakers. A prosecutor told her that, at that point, Mr. Garland’s time in office was limited and that he wanted to see the release of the report “satisfied during his tenure.”

Judge Cannon seemed annoyed by that answer in her ruling on Tuesday, deriding it as “the bare wishes of one attorney general.”

“These statements do not reflect well on the department,” she wrote.

Mr. Trump’s lawyers and the other defense lawyers in the case have vehemently fought the release of the report to anyone outside the Justice Department. They have claimed that it contains “false and derogatory” information that Mr. Trump’s congressional adversaries could use to undermine “his ability to govern our nation moving forward.”

The lawyers have also complained that the volume implicates some unnamed “anticipated” members of Mr. Trump’s administration — a potential reference to Kash Patel, Mr. Trump’s pick to run the F.B.I. Mr. Patel was forced to testify to a grand jury in the documents case after he initially refused to answer questions by asserting his Fifth Amendment right against self-incrimination.

Judge Cannon, in her order, confirmed that the documents volume contained new, and potentially damaging, information that “has not been made public in court filings.”

That included “voluminous and detailed” discovery evidence about the allegations that Mr. Trump had illegally retained reams of classified materials after he left office in 2021. Some of that information, Judge Cannon wrote, described Mr. Trump’s “other bad acts” that were not charged in the indictment — a possible reference to other instances when he mishandled classified materials.