Crucially, we don’t know whether Barr concluded that the president didn’t obstruct justice or that he couldn’t obstruct justice.Carolyn Kaster / AP

We cannot yet see the report that Special Counsel Robert Mueller submitted to Attorney General William Barr on Friday. But we can see its shadow in the four-page letter Barr sent to the chairs and ranking members of the House and Senate Judiciary Committees on Sunday afternoon. The letter will be touted as vindication by President Donald Trump and his supporters, but will do little to bridge the partisan divide over Mueller’s nearly two-year investigation, and will inspire more vociferous demands to release the entire report.

Barr’s letter thoroughly quelled some of the fondest hopes of the anti-Trump “resistance.” The letter revealed that Mueller closed his investigation without recommending more criminal charges, and that no further indictments are under seal, as some had speculated. That’s a great relief for Trump and his family and associates, but it’s not the end of their federal criminal jeopardy. Barr also pointed out that Mueller “referred several matters to other offices for further action.” For instance, the special counsel sent the investigation of Michael Cohen’s hush-money payments to Stormy Daniels to the U.S. Attorney’s Office for the Southern District of New York, which secured Cohen’s guilty plea for federal campaign-finance violations. That office is still actively investigating the matter—we know this because it carefully redacted the details of the investigation when it released the Cohen search warrants last week. But the special counsel’s investigation was the most prominent legal threat to the president and his family, and its closure without further indictments is a major victory for him.

Next, Barr reported that the special counsel concluded that Russia attempted to interfere with the 2016 presidential election. That interference involved disinformation campaigns, efforts to sow “social discord” online, hacking the Hillary Clinton campaign and the Democratic Party, and distributing misappropriated emails through WikiLeaks. But crucially, Mueller reported that his investigation “did not establish that members of the Trump campaign conspired or coordinated with the Russian government in its election interference activities,” whether expressly or tacitly. To use the popular cable-news vernacular, Mueller did not establish “collusion.” (Never mind that collusion is not a legal term, and that the special counsel’s mission was to investigate “links and/or coordination” with the Russians.)

Trump’s triumphant supporters notwithstanding, we don’t yet know what that means. When prosecutors say that an investigation “did not establish” something, that doesn’t mean that they concluded it didn’t happen, or even that they don’t believe it happened. It means that the investigation didn’t produce enough information to prove that it happened. Without seeing Mueller’s full report, we don’t know whether this is a firm conclusion about lack of coordination or a frank admission of insufficient evidence. The difference is meaningful, both as a matter of history and because it might determine how much further Democrats in Congress are willing to push committee investigations of the matter.

The other big reveal in Barr’s letter is that Mueller “determined not to make a traditional prosecutorial judgment” about whether the president obstructed justice over the course of the two-year investigation of Russian interference in the election. Instead, Mueller laid out the relevant evidence “on both sides” of the issue, but did not resolve what the special counsel saw as the “difficult issues” of fact and law concerning “whether the President’s actions and intent could be viewed as obstruction.” Mueller’s report “does not conclude that the President committed a crime, it does not exonerate him.” Mueller punted.

Why would Mueller spend so much time investigating obstruction of justice but not reach a conclusion? We won’t know until we read his report. But Mueller, a career G-man, is fundamentally legally conservative. That means he has a narrow view of his own role and a healthy respect for the authority of the other branches of government. He might believe that the evaluation is so inherently political that no conclusion he could offer would ever be seen as legitimate, and that the matter is better resolved through Congress’s constitutional authority to impeach (or not) the president. Even if Mueller didn’t make an explicit recommendation, we’ll probably be able to infer his conclusions by reviewing how he marshaled the evidence for and against guilt. Prosecutors, as a rule, are not good at neutral renditions of facts.

The attorney general showed no such circumspection. In less than 48 hours, he and Deputy Attorney General Rod Rosenstein—who supervised Mueller for most of his investigation—“concluded that the evidence developed during the Special Counsel’s investigation is not sufficient to establish that the President committed an obstruction-of-justice offense.” Though Barr emphasized that he and Rosenstein had been involved in evaluating the status of the investigation for months, and that they consulted the Office of Legal Counsel and other Department of Justice experts, this conclusion reflects startling and unseemly haste for such a historic matter.

Crucially, we don’t know whether Barr concluded that the president didn’t obstruct justice or that he couldn’t obstruct justice. Well before his appointment, Barr wrote an unsolicited memo to Rosenstein arguing that Mueller’s investigation was “fatally misconceived,” to the extent that it was premised on Trump firing former FBI Director James Comey or trying to persuade Comey to drop the investigation of Michael Flynn, Trump’s first national security adviser. Barr’s memo was a forceful exposition of the legal argument that the president cannot obstruct justice by exercising certain core powers such as hiring or firing staff or directing the course of executive-branch investigations. So although Barr’s letter to Congress says that he and Rosenstein found no actions that constituted “obstructive conduct” undertaken with the requisite corrupt intent, we don’t know whether he means that Trump didn’t try to interfere with an investigation, or that even if he did, it wasn’t obstruction for a president to do so. Democrats in Congress will want to probe that distinction—as they should.

Mueller’s report was initially confidential under Department of Justice regulations governing the special counsel. In Sunday’s letter, Barr said his goal was to release as much of it as possible consistent with the law. In particular, he noted that the report includes information about matters occurring before a grand jury that are secret as a matter of federal law, and that some other references in the report might reveal the status of ongoing investigations. Barr must abide by his promise to resolve those questions promptly and in favor of as much disclosure as the law permits. It’s impossible to evaluate the results of Mueller’s investigation—and their legal, political, and historical significance—without the details.

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