Lynch, or her designee, had the power to order Comey not to send his letter. Media reports say unnamed Justice officials warned him that it would violate policies against prosecutorial action too close to an election, but they stopped short of an express command to stand down — for fear of precipitating an even bigger election-eve crisis.

The net effect of so much irregular procedure has been to convince partisans of all stripes, possibly lastingly, that these vital institutions cannot be trusted, and therefore must be fought over.

If Trump wins, Democrats would consider it an FBI-engineered victory. If Clinton wins, she would face the awkward predicament of working on anti-terrorism and other vital efforts with an FBI director still pursuing a Republican-encouraged investigation of her emails. Comey’s term expires in 2023.

Many Democrats (and not a few Republicans) think Comey should resign, in part to head off that predicament. But that would probably lead to a new problem: a partisan impasse in the Senate over replacing the FBI director, just like the one we already have involving Justice Antonin Scalia’s former seat on the Supreme Court.