The reason for using any of these models, especially the special counsel one, is really the opposite of Mr. Barr’s apparent goal. They are designed to insulate from politics serious investigative work that needs to be done. But Mr. Barr has asked Mr. Durham to cover ground that has already been explored in detail by the department’s inspector general. As if that wasn’t enough, Mr. Barr and Mr. Durham denigrated an element of the inspector general’s findings even as Mr. Durham’s own investigation continued, in a remarkable break with a longstanding department norm of not commenting on a continuing criminal investigation and not simply rejecting the findings of an inspector general.

So far as anyone can tell, after months of work, Mr. Durham’s effort appears not to be investigative work that requires insulation from politics but political work that Mr. Barr now wants to insulate from investigative scrutiny. That stands the special counsel model on its head and underscores why he should not receive the “special counsel” designation.