This post has been updated, 5:20 p.m.

Attorney General William P. Barr’s testimony Wednesday before the Senate Judiciary Committee was an exercise in what committee member Sheldon Whitehouse (D-R.I.) accurately described as “masterful hairsplitting.”

But give Barr credit for making one thing clear: We must hear from special counsel Robert S. Mueller III, directly and publicly.

At one point, under Whitehouse’s questioning about the special counsel’s report, the attorney general said: “I don’t want to characterize Bob’s thought process here.” Except he did. Again and again. Most strikingly, Barr told a blatant falsehood about Mueller’s reaction to the attorney general’s efforts to portray the report as an exoneration of President Trump. Barr did that twice — first in a four-page letter March 24 summarizing the findings of the report, and then in a news conference shortly before the 448-page document was made public on April 18.

"Mueller had never told me that the expression of the findings was inaccurate,” Barr said during his testimony. “I certainly am not aware of any challenge to the accuracy of the findings.”

Any fair read of the Mueller report, even in its redacted form, shows that it was not what Barr portrayed it to be. While the special counsel did not find any evidence that the president and his campaign colluded with Russia to sway the results of the 2016 election, he did cite instances in which Trump potentially broke the law with attempts to obstruct the investigation.

And now, thanks to reporting by my colleagues here at The Post, we also know that Mueller personally expressed his objection to Barr’s original letter.

“The summary letter the [Justice] Department sent to Congress and released to the public late in the afternoon of March 24 did not fully capture the context, nature, and substance of this office’s work and conclusions,” Mueller wrote. “There is now public confusion about critical aspects of the results of our investigation. This threatens to undermine a central purpose for which the Department appointed the Special Counsel: to assure full public confidence in the outcome of the investigations.”

So now, Barr has not only mischaracterized Mueller’s report, he has doubled down by mischaracterizing the special counsel’s reaction to his twisting of the findings. The attorney general has now proved beyond any doubt how little regard he has for his own credibility, even when he is under oath. After first claiming he was unaware of any objections by Mueller, Barr later switched gears and referred to special counsel’s letter as “a bit snitty.” The attorney general even suggested it may have actually been written by someone on the Mueller’s staff.

Judiciary Committee Chairman Lindsey Graham (R-S.C.) now wants to close the book, and says he will not call Mueller before the committee. “It’s over,” he said.

Graham is wrong. Barr has created an imperative. Mueller must testify. The sooner, the better.

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