Did President Trump have a right to be annoyed with Jeff Sessions for recusing himself? A plausible case can be made that Sessions didn’t have to do it, but then there’s an equally plausible case that he did. The real grounds for criticizing Sessions lie elsewhere: once he decided that he would need to recuse himself, Sessions had a duty to make sure that a replacement was on hand who was up to the task that Sessions had sidestepped. That he did not do. Rod Rosenstein has made one grievous mistake after another, with no end in sight.

Rosenstein’s most important error was the complete incoherence of his statement of the scope of the investigation in his order of May 17 appointing Robert Mueller as Special Counsel: “…any links and/or coordination between the Russian government and individuals associated with the campaign of President Donald Trump.” Here he specified no particular actor (there are scores that this might refer to) nor particular actions, times or places, nor even crimes, because “links” and “coordination” are not in themselves criminal.

Think about what Special Counsel was being asked to do. Absent any specific allegations, he would need to do something akin to proving a negative. Proving that a specific event actually happened is possible because the details of that event tell us where to look, but proving that something never happened is impossible because it could have happened at any time or place and by action of any person. We could never exhaust all the possibilities. Similarly, for Special Counsel to reach the conclusion that no coordination ever took place is a logical impossibility: it would require that he retroactively monitor every moment of the life of every person involved in the Trump campaign, and that he seize every conceivable record of all such people. If he only asked for phone records, he would miss evidence in emails, but if he also asked for emails, he would miss evidence in written correspondence. And if he asked only for all of these, he would miss what diaries can tell him. And then there are text messages… But even all of this would not be enough: he would need to look into what other people’s records might tell him about each person’s activities. (But which other people? How many?) Mueller would have to do this for every single one of Trump’s campaign staff.

But since he can’t cite any criminal act, he has no legal grounds to get any of this evidence. The Code of Federal Regulations, Title 28, Section 600, provides that Special Counsel shall have no special powers but only those of any other U.S. Attorney, and that he must follow all rules and regulations of the Justice Department. Like every other U.S. Attorney, he’d have to show why he needs records, and having no alleged crime to base his request on, he can’t.

To get anything at all he’d have to proceed unethically and in violation of the law. There is a now well-known Special Counsel tactic: focus on a person who has been close to the president, seize all his records, then look for any infraction whatsoever that will give you the chance to squeeze him by offering immunity in exchange for something that will damage the president. That seems to be what Mueller is doing:  he has managed to persuade a gullible judge that, contrary to the explicit provisions of Section 600, the mystique of a Special Counsel’s investigation gives him the power to seize large quantities of evidence from Paul Manafort without evidence of a crime. Let’s be clear about this: it amounts to trying to find out whether at some moment or other on some day or other and in some place or other Manafort just might have committed some crime or other. The U.S. Constitution protects us all from unreasonable searches and seizures, and this is the ultimate unreasonable search. Seeing this, Rosenstein ought to have intervened to stop this ugly behavior. But how can he? The charge he gave Mueller virtually leaves him no alternative.

Under the currently operative rules, a Special Counsel is not completely independent: he has a supervisor, the acting attorney general. But Rosenstein either can’t or won’t supervise Mueller. Many have pointed out that Mueller’s appointees include large numbers of prominent donors to the Clinton campaign, with none on the other side. Rosenstein should long since have told Mueller to stop doing this, both because it’s unfair and because it has undermined public confidence in his investigation. More important still, his appointees have the most flagrant conflicts of interest. Take simply one case, that of Jeannie Rhee: Rhee worked for the Clinton Foundation, but she was also Hillary Clinton’s personal lawyer in the matter of her emails. Mueller saw no problem in hiring her as one of his senior staff. Yet the hacking of DNC emails allegedly by the Russians is at the very center of Muller’s investigation, and Rhee has direct prior partisan involvement precisely there, where it matters most. She doesn’t just have a conflict -- she has the worst possible conflict of interest. Rosenstein should have told Mueller to get rid of Rhee immediately, and to make sure that none of his staff are conflicted. But he does nothing

It’s fair to ask at this point: what does this episode tell us about Mueller’s fitness for the position to which he has been appointed? If he didn’t notice this and other similar conflicts, he is incompetent. But if he knew about them and still wanted such people on his team, then he must be a ruthless partisan, and a man completely lacking in integrity. An investigation of this kind looks above all for corruption in government. Haven’t we already found it in these people being hired by this Special Counsel?

Many other circumstances surrounding the Mueller appointment throw doubt on Rosenstein’s ability to do the job Sessions left to him. In his June 8 testimony James Comey said that he leaked a memo about his conversation with President Trump in order to whip up public pressure for the appointment of a Special Counsel. In essence, he freely admitted that he was trying to stampede Rosenstein into a hasty, ill-considered action -- and he succeeded. Rosenstein allowed himself to be manipulated, and the utter incoherence of his order is the measure of how ill-considered his action was. Worse still, Comey publicly humiliated Rosenstein by explaining just how he had played him: now everyone knew that an investigation of extraordinary national importance had been initiated by sleazy and devious behavior on Comey’s part. The onus was now on Rosenstein to repair the damage done by his failure to understand how he was manipulated. He did nothing.

Yet another problem created by Rosenstein’s panicked action was his choice of Mueller to head the investigation. Since Comey’s firing was an important part of the whole affair, Mueller’s notoriously close personal and professional relationship with Comey should have ruled him out. But by the time that Comey (in his June 8 testimony) revealed the full depth of his antagonism to the President, that point had become much stronger. Mueller’s credibility had by then completely evaporated. But Rosenstein still did nothing.

Now at last it has come to light that the hacking and dissemination of the DNC emails was done not by the Russians (as Obama’s intelligence chiefs falsely assured us with such smug confidence) but by a DNC insider. This new revelation removes the only factual basis that has ever existed for the Mueller investigation. And still, Rosenstein does nothing.

When he recused himself, Attorney General Sessions had a duty to ensure that the person who would stand in for him was up to the job. Clearly, Rosenstein was not. He has seemed like the sorcerer’s apprentice, who couldn’t resist exercising his master’s powers, but didn’t really understand what he was setting in motion. As things have got more and more out of control, he has seemed powerless to stop them. It’s time for the boss to return and boot the apprentice out of his study.

John M Ellis is Distinguished Professor Emeritus at the University of California, Santa Cruz.