The Justice Department’s sustained effort to criminally prosecute former FBI Director James Comey has now produced a measurable institutional cost: more than a half-dozen prosecutors have been demoted or pushed out of the U.S. Attorney’s Office for the Eastern District of Virginia, others are weighing departures, and at least one major case has been disrupted. The campaign against Comey, spanning two separate indictments across nine months, has accomplished less legally than it has damaged the office pursuing it.