This report has been updated.

Robert S. Mueller III just delivered the long-awaited and highly anticipated report on his Russia investigation to Attorney General William P. Barr.

Welcome to one of the most anti-climactic moments in modern American political history.

The truth is we don’t really know anything we didn’t know a few minutes ago, and it’s still massively unclear what we’ll learn about Mueller’s findings. In his letter to Congress Friday, Barr wrote that he remains “committed to as much transparency as possible, and I will keep you informed as to the status of my review.” He said he could deliver a summary as early as this weekend.

But it’s unclear what that will actually look like.

As Barr explained in his confirmation hearing back in February, once he received the report, he planned to summarize the parts he can for Congress and the public within the constraints of the law and Justice Department guidelines.

What does that mean? What happens next? Here’s a little primer to consult as we wait ... again.

What constrains Barr

There are a few basic things Barr may have to withhold from public view, and even potentially from Congress.

Federal Rule of Criminal Procedure 6 says that details of the investigation must be kept secret unless they are revealed as part of a court order related to an indictment or other proceeding. Grand jury rules prohibit the disclosure of information obtained via that method — a method Mueller has undoubtedly used extensively — unless actual charges are filed. And Barr will also have to review the report for any classified information.

It is expected that this review process could take days or even weeks.

The Catch-22

But this creates an unusual and problematic circumstance when it comes to President Trump. The Justice Department has affirmed its guidelines prohibit the indictment of a sitting president, so how will information about Trump be handled? If Trump can’t be indicted, and Barr can only disclose information related to actual charges, does that mean he can’t say much of anything about Trump’s conduct and potential obstruction of justice? Trump said Wednesday that he is fine with the full report going public, but does that even matter?

In short, we don’t know what happens. But it’s difficult to believe Barr and the Justice Department won’t have to say something about whether Mueller believed Trump’s actions rose to the level of crimes, even if he can’t be charged.

After all, Congress is the body charged with holding a president accountable, through impeachment proceedings. So it would seem at least they would somehow need to be made aware of the information required to make such decisions.

A road map? Separate reports? Releasing the whole thing?

One option that has been floated for Barr is releasing separate reports. Former Justice Department officials have suggested he could deliver two reports to Congress: One with unclassified information that could be given to all lawmakers (and would presumably leak to the public), and a separate one that would be given to a much-smaller universe of congressional leaders, such as House Intelligence Committee Chairman Adam B. Schiff (D-Calif.) and House Judiciary Committee Chairman Jerry Nadler (D-N.Y.), who is in charge of any impeachment efforts.

But even then, the rules described above could get in the way.

Another option would be to take a page out of history. When confronting a somewhat similar set of circumstances during Watergate, special prosecutor Leon Jaworski used a workaround: Rather than make recommendations to Congress and pass along all his findings, he transmitted through a grand jury what became known as the Watergate “road map.” It was a bare-bones set of facts and guideposts for them to conduct their own inquiries and draw their own conclusions. The move was authorized by a federal judge and could provide an important legal precedent for Barr.

A third eventual result would be that the full report, or something amounting to it, eventually finds its way out. House Democrats have said they will press for the whole thing. The House voted 420-0 to make the report public, and Trump said this week, “Let people see it.” But how Congress feels may not matter. They can’t simply pass a law to force the report’s release, given that would conflict with other federal laws. If they were to get extensive details of Mueller’s findings, it would likely have to come through the legal system in some fashion. They could seek a court order. They could subpoena Mueller’s documents. They could call Mueller to testify. They could do all of the above and more.

In short, Mueller has conducted a highly secretive investigation, whose inner workings have often been revealed only months after key events took place. And just as we don’t really know what he’s found, we don’t know what the endgame will be even now that the report has been written and transmitted. This could go in a whole bunch of different directions, with a relatively new attorney general in charge of it all.