It was an early case of Donald J. Trump seeking retribution through the Justice Department.
In the first year of Mr. Trump’s first presidency, Attorney General Jeff Sessions appointed a top federal prosecutor to review whether the F.B.I. had failed to fully pursue investigations involving Hillary Clinton, including an inquiry into the Clinton Foundation’s ties to a Russian uranium mining operation.
The appointment of the prosecutor, John W. Huber, the U.S. attorney in Utah, was championed by many on the right eager to turn the spotlight away from Mr. Trump’s ties to Moscow. But when Mr. Huber’s work ended years later with no charges or public report, Mr. Trump publicly called him a “garbage disposal unit for important documents.”
As Mr. Trump begins filling out his administration and putting his stamp on Washington again, few issues loom larger than the resilience of the Justice Department’s tradition of independence and its commitment to the rule of law.
Mr. Trump’s grievance-laden campaign rhetoric has left many current and former agency officials fearful that he will seek to turn it into a department of revenge aimed at foes inside and outside government.
They said they worried that Mr. Trump’s past experiences with the Justice Department mean he is less likely this time to settle for an investigation like Mr. Huber’s — one that leads to little punishment or pain for anyone.
In an interview, Mr. Huber characterized his work during Mr. Trump’s first term as a sign of the Justice Department’s ability to withstand any political pressure.
