The deputy attorney general, Rod J. Rosenstein, suggested last year that he secretly record President Trump in the White House to expose the chaos consuming the administration, and he discussed recruiting cabinet members to invoke the 25th Amendment to remove Trump from office for being unfit.

Rosenstein made these suggestions in the spring of 2017 when Trump’s firing of James B. Comey as FBI director plunged the White House into turmoil. Over the ensuing days, the president divulged classified intelligence to Russians in the Oval Office, and revelations emerged that Trump had asked Comey to pledge loyalty and end an investigation into a senior aide.

Rosenstein was just two weeks into his job. He had begun overseeing the Russia investigation and played a key role in the President’s dismissal of Comey by writing a memo critical of his handling of the Hillary Clinton email investigation. But Rosenstein was caught off guard when Trump cited the memo in the firing, and he began telling people that he feared he had been used.

Rosenstein made the remarks about secretly recording Trump and about the 25th Amendment in meetings and conversations with other justice department and FBI officials.

Several people described the episodes in interviews over the past several months, insisting on anonymity to discuss internal deliberations. The people were briefed either on the events themselves or on memos written by FBI officials, including Andrew G. McCabe, then the acting bureau director, that documented Rosenstein’s actions and comments.

President Donald Trump addresses the crowd during a campaign rally on Friday. AP Photo

None of Rosenstein’s proposals apparently came to fruition. It is not clear how determined he was about seeing them through, though he did tell McCabe that he might be able to persuade Attorney General Jeff Sessions and John F. Kelly, then the secretary of homeland security and now the White House chief of staff, to mount an effort to invoke the 25th Amendment.

The extreme suggestions show Rosenstein’s state of mind in the disorienting days that followed Comey’s dismissal. Sitting in on Trump’s interviews with prospective FBI directors and facing attacks for his own role in Comey’s firing, Rosenstein had an up-close view of the tumult.

Rosenstein appeared conflicted, regretful and emotional, according to people who spoke with him at the time.

Rosenstein disputed this account.

“The New York Times’s story is inaccurate and factually incorrect,” he said in a statement. “I will not further comment on a story based on anonymous sources who are obviously biased against the department and are advancing their own personal agenda. But let me be clear about this: Based on my personal dealings with the president, there is no basis to invoke the 25th Amendment.”

A justice department spokeswoman also provided a statement from a person who was present when Rosenstein proposed wearing a wire. The person, who would not be named, acknowledged the remark but said Rosenstein made it sarcastically.

But according to the others who described his comments, Rosenstein not only confirmed that he was serious about the idea but also followed up by suggesting that other FBI officials who were interviewing to be the bureau’s director could also secretly record Trump.

McCabe declined to comment. His memos have been turned over to the special counsel, Robert S. Mueller III, in the investigation into whether Trump associates conspired with Russia’s election interference.