The Justice Department declined to comment.

Mr. Cohen-Watnick, 31, served briefly at the start of the Trump administration as the senior director for intelligence for the National Security Council, overseeing covert action and other intelligence programs. He was brought on by Michael T. Flynn, President Trump’s first national security adviser. But some former officials criticized Mr. Cohen-Watnick, a former clandestine officer in the Defense Intelligence Agency, as too young for the job, which is usually filled by C.I.A. veterans.

Mr. Cohen-Watnick was ousted in August 2017 as part of changes in the White House, one of several appointees of Mr. Flynn who were removed by his replacement, Lt. Gen. H.R. McMaster.

National Security Council aides usually draw little public scrutiny, but Mr. Cohen-Watnick was swept up in the tumult of early 2017 when Mr. Trump accused the previous administration, without evidence, of wiretapping his phones at Trump Tower.

Mr. Trump’s allegations were bolstered by Representative Devin Nunes of California, the Republican chairman of the House Intelligence Committee, who said he had evidence that Mr. Trump’s communications were incidentally swept up in surveillance of foreigners by American spy agencies.

Mr. Nunes did not divulge the sources of this information, but American officials later told The New York Times that Mr. Cohen-Watnick, at the instruction of two senior White House officials, helped print intelligence reports that later served as Mr. Nunes’s proof.