The F.B.I. began investigating a New York Times reporter last month after she wrote about the bureau’s director, Kash Patel, using bureau personnel to provide his girlfriend with government security and transportation, according to a person briefed on the matter.

Agents interviewed the girlfriend, queried databases for information on the reporter, Elizabeth Williamson, and recommended moving forward to determine whether Ms. Williamson broke federal stalking laws, the person said.

Those actions prompted concerns among some Justice Department officials who saw the inquiry as retaliation for an article that Mr. Patel and his girlfriend, Alexis Wilkins, did not like, and who determined there was no legal basis to proceed with the investigation, according to the person briefed on the matter.

In response to questions from The Times this week, the F.B.I. said that “while investigators were concerned about how the aggressive reporting techniques crossed lines of stalking,” the F.B.I. is not pursuing a case.

The scrutiny of Ms. Williamson is an example of the Trump administration examining whether to criminalize routine news gathering practices that are widely considered protected by the First Amendment.

Journalists are more often caught up in criminal investigations as potential witnesses when the authorities are trying to determine who leaked them classified information.