Editor’s Note: This is the first article in a two-part series; the second will appear tomorrow.Robert Mueller’s congressional testimony was such a bumbling fiasco that it was easy for a viewer to be confused -- and stay that way -- about the main bone of Democratic contention regarding his report: the “OLC guidance” that prevents the Justice Department from charging a president with crimes while he is in office. Specifically, how did it factor into the special counsel’s decision -- or, rather, non-decision -- on the main question he was appointed to answer: Did President Trump obstruct justice? How did the special counsel’s dubious reliance on it as a rationale for abdicating on this question affect the publication and ramifications of the Mueller report?We’ve plowed this ground before, but it is worth revisiting. We will do that in this weekend’s two-part series. This is Part 1.The OLC GuidanceThe OLC is the Office of Legal Counsel, the lawyers’ lawyers in the Justice Department who formulate policies that guide federal prosecutors throughout the United States. The OLC guidance at issue in the Mueller investigation is the prohibition on indicting a sitting president. This rule is said to be derived from constitutional and prudential considerations.I do not believe the guidance is sound. But that’s beside the point: The guidance is binding on Justice Department lawyers, period. That means it is also binding on special counsels. By regulation, they are firmly in the Justice Department chain of command.Consequently, the OLC guidance applied to Mueller’s investigation of President Trump. In particular, it was relevant to the obstruction aspect of the probe, which was always a criminal investigation. (For reasons that need not divert us, the “collusion” part of the case was pretextually conducted as a counterintelligence investigation.)Because (a) the president was the principal subject of the obstruction probe and (b) the objective of such a criminal investigation is to indict wrongdoers, the pertinence of the OLC guidance is obvious. The question is: What is the effect of its application?Until Mueller’s investigation, I would have thought this was straightforward. The president may not be indicted while in office. Notice: This does not mean the president may not be investigated while in office; nor does it mean the president may never be indicted. The investigation may proceed while a president serves his term; if the prosecutor finds sufficient evidence to charge a criminal offense, an indictment may be obtained from the grand jury as soon as a president is out of office.That is, just as in any other case, the criminal allegation must be investigated, and a charging decision must be made. The only difference is: If the case is judged worthy of indictment, the indictment must be deferred until a president leaves office. This is key: The point of the guidance is not to give presidents a special defense that is unavailable to other Americans. Presidents are not above the law. The guidance is not of substantive significance; it is merely a matter of timing: In deference to the awesome responsibilities of the presidency, we do not permit the chief executive to be burdened during his term by the consuming effort and anxiety of defending against a criminal charge. Presidents are not spared forever from these burdens that other accused persons must bear, just while in office.Democrats Push Mueller to Contradict ReportThat, however, is not how the OLC guidance was construed by Mueller -- or, I should say in light of Mueller’s patent unfamiliarity with the Mueller probe, by whoever on the special counsel staff was actually running the investigation.The staff took the position that the OLC guidance did not just forbid the indictment of a sitting president. Its logic, they insisted, rendered it impermissible even to consider whether there was sufficient evidence to indict a sitting president.That’s ridiculous. But before we come its incoherence and disingenuousness, let’s deal with why the special counsel’s theory was critical to Mueller’s testimony.Democrats would like to impeach the president. The best way to lay the groundwork for that would be to establish Trump’s commission of a felony. To be sure, presidential misconduct need not qualify as a penal-law felony to qualify as an impeachable offense. Yet, if an abuse of power does amount to a felony, the case for impeachment is much stronger. Therefore, Democrats want to be able to argue that Mueller, the renowned prosecutor who vigorously investigated for nearly two years, authoritatively concluded that Trump committed felony obstruction.Of course, Mueller made no such finding. For Democrats, the next best thing is to establish that Mueller in effect concluded that Trump committed felony obstruction but was prevented from filing charges by a technicality. That is, they wanted Mueller to testify that if it were not for the OLC guidance, he would have called for the president’s indictment.The problem: That’s not what Mueller’s report says. In the report, the special counsel took the position that, because of the OLC guidance, it would have been impermissible for prosecutors even to consider indicting the president. So, he did not, in effect, find felony obstruction. If you believe the report on this (I don’t, by the way), the special counsel’s staff never weighed the evidence for purposes of making a charging decision, one way or the other.The main reason Democrats foolishly pressured Mueller into testifying was the hope that he would abandon the restraint of his report. They calculated that they could push him or trick him into saying that but for the OLC guidance, he would have charged the president.Fleetingly, after a couple of excruciating hours, Democrats got this concession out of the badgered and befuddled special counsel during questioning by Representative Ted Lieu (D., Calif.). But Representatives Debbie Lesko (R., Ariz.) and John Ratcliffe (R., Texas) swooped in to clean up the mess. So did the special counsel himself. Right after the lunch recess, having clearly been coached regarding his blunder, Mueller clarified (if you can call it that) that he had misspoken, and he reaffirmed “his” report. Bottom line: Mueller would not testify that, if not for the OLC guidance, the president would have been indicted. He says his team never considered indicting Trump, never evaluated whether there was enough evidence to charge obstruction.The Distortion of the OLC Guidance by Mueller’s StaffLegally, Mueller’s interpretation of the OLC guidance is absurd. A prosecutor has only one job: to determine whether there is sufficient evidence to prove guilt beyond a reasonable doubt. This is elucidated by federal regulations: The special counsel must prepare “a confidential report explaining the prosecution or declination decisions.” There is no third way. There is no authorization to evade what Mueller’s transgressive staff described as the “traditional,” “binary” prosecutorial decision to charge or not to charge.The regs design the special counsel to be an ordinary federal prosecutor. When I was a line prosecutor, my boss was the district U.S. attorney. Analogously, the special counsel is a line prosecutor whose boss is the attorney general. My job was to investigate cases and make a recommendation to my chain of command to indict or decline prosecution. Mueller’s job was to make that same recommendation to the AG. If Mueller had found sufficient evidence to file charges, it would then have been up to the AG to decide (a) whether to accept that recommendation and (b) whether to delay indictment until the president left office, in accordance with the OLC guidance.That is to say: The OLC guidance on the timing of an indictment has nothing to do with whether there is a prosecutable case. There is no justification for freighting the charging decision with the timing issue.Again, the OLC guidance does not say the president may never be indicted, just that he may not be indicted while in office. Plainly, then, regardless of when an indictment is filed, somebody has to make the decision about whether an indictment should be filed. Under Mueller’s harebrained theory, we should not expect the prosecutor who spends $40 million investigating the case for two years to make this call; rather, some other prosecutor should reinvent the wheel -- retrieve the file, reassemble the evidence, get up to speed on the record, re-interview all the witnesses, etc. -- after Trump leaves office, whether that’s a year and a half or five and a half years from now. We should just pretend the ride Mueller & Co. have taken us on since May 2017 never happened.That’s batty. So what is Mueller’s rationale for such a procedure? Well, that’s even more laughable: Mueller would have you think he’s just trying to protect President Trump.A likely story, no? We’ll see when we explore it in Part 2, tomorrow.