WASHINGTON - There is a mountain of evidence that President Trump obstructed justice. There is considerable evidence that the Trump campaign embraced and encouraged Russia's attempt to meddle in the 2016 election. Special counsel Robert Mueller laid out the facts -- and now Congress has a solemn duty to confront them.

Contrary to what Trump says, the long-awaited Mueller report is not an exoneration. The report makes that clear more than once, verbatim, including this passage in Part II: "Accordingly, while this report does not conclude that the President committed a crime, it also does not exonerate him."

Nor does the report indict Trump for obstruction. But that is because Mueller took as his starting point the Justice Department opinion that a sitting president should not be made to face criminal charges. "If we had confidence after a thorough investigation of the facts that the President clearly did not commit obstruction of justice, we would so state," Mueller wrote. "[W]e are unable to reach that judgment."

Trump and his apologists will try to paint the report as equivocal, but the evidence it cites strikes me as definitive. One representative passage from Part II, page 157:

"Our investigation found multiple acts by the President that were capable of exerting undue influence over law enforcement investigations, including the Russian-interference and obstruction investigations. The incidents were often carried out through one-on-one meetings in which the President sought to use his official power outside of usual channels. These actions ranged from efforts to remove the Special Counsel and to reverse the effect of the Attorney General 's recusal; to the attempted use of official power to limit the scope of the investigation; to direct and indirect contacts with witnesses with the potential to influence their testimony."

Mueller does not explicitly say that Congress must now judge the president's conduct. But he draws a detailed road map for such an exercise, including not just the voluminous evidence he gathered but also the legal reasoning for viewing some of Trump's actions -- including his firing of then-FBI Director James Comey and his attempt to get then-White House Counsel Don McGahn to fire Mueller -- as patently illegal.

The Mueller report was released Thursday by Attorney General William Barr, who, in the process, destroyed what was left of his own credibility. Pre-spinning the document before anyone had a chance to read it, Barr parroted Trump's favorite talking point and said Mueller found no "collusion" between the Trump campaign and the Russians. The report, however, says no such thing. It notes that "collusion" is not a federal offense and seeks instead to determine whether there is evidence of conspiracy, which is a statutory crime. Mueller did find such evidence, but not enough to bring criminal charges.

Barr flat-out lied when he said that Mueller's decision not to charge Trump had nothing to do with the Justice Department opinion that effectively gives immunity to a sitting president. The report states clearly that this opinion has (BEG ITAL)everything(END ITAL) to do with Mueller's choice to lay out the evidence without reaching a conclusion.

Barr said he and Deputy Attorney General Rod Rosenstein decided to declare the matter of obstruction closed because Trump was understandably "frustrated and angered" at the very existence of the investigation, and thus may not have had the requisite intent to commit a crime. But Barr was confusing two different concepts, motive and intent. Trump's motive for trying to fire Mueller, for example, may well have been anger and frustration. But his legal intent may have been to obstruct justice.

Barr so embarrassed himself that Fox News anchor Chris Wallace seemed appalled. "The attorney general seemed almost to be acting as the counselor for the defense, the counselor for the president, rather than the attorney general, talking about his motives, his emotions," Wallace said. "Really, as I say, making a case for the president."

The report notes that Trump "lambasted" former Attorney General Jeff Sessions when Sessions recused himself from involvement in the Mueller probe, telling him "'you were supposed to protect me' or words to that effect." Barr obviously is determined not to make the same mistake.

Now responsibility shifts to Congress, and House Speaker Nancy Pelosi has a decision to make.

The Mueller report establishes that the Russians massively interfered with our election and that the Trump campaign cheered and encouraged that hostile act. It lays out ample evidence that Trump obstructed justice. Only Congress can hold the president accountable.

Thus far, Pelosi has resisted any move toward impeachment. Politically convenient or not, that's where Mueller's road map leads.

Eugene Robinson's email address is eugenerobinson@washpost.com.