President Donald Trump officially disapproved of special counsel Robert Mueller testifying to Congress over the weekend, tweeting Sunday that Democrats are “looking for a redo because they hated seeing the strong NO COLLUSION conclusion.” “Bob Mueller should not testify,” he added. “No redos for the Dems!” The tweet marked a reversal for Trump, who had previously left it up to Attorney General William Barr to decide on Mueller's testimony—and apparently his advisers aren't necessarily on board with the change. Politico reported Monday that many on the Trump team were “surprised” by the tweet, and immediately attempted to downplay its meaning. “He is not signaling anything other than, as an innocent man so found by Mr. Mueller, he just wants this over,” Trump's informal legal adviser Joe diGenova told Politico. “The president tweets all the time. I’d assume now after three years people would be used to it.”

Per Politico, the White House has “all but ignored” the controversial tweet, which could pave the way for an “unpredictable” court challenge should Trump actually try to block Mueller's testimony. “Where did he say he would block [Mueller] from testifying? I know that’s what the media said — but where did he say it?” one White House aide said. Trump lawyer Rudy Giuliani similarly denied Trump was necessarily saying he'd block the testimony, claiming, “I think I’d have to hear the words ‘We’re invoking executive privilege’ to know they’ve come to that conclusion.” Others in the Trump camp, however, suggested that the president hasn't actually ruled out using executive privilege to halt Mueller's testimony or testimony from his deputies, who the president referred to Sunday as “18 Trump Hating Angry Democrats.” “The administration keeps sinking lower and lower. And I imagine they really will try and stop Mueller from testifying,” Democratic Rep. Jamie Raskin told Politico.

Trump's tweet shook up Mueller's already much-hyped congressional testimony, which Democratic lawmakers have said they would like to take place on May 15. “This certainly seems like the biggest hearing for Congress since Watergate,” Ted Kalo, former Democratic general counsel to the House Judiciary Committee, told Politico. “His ability to explain his conclusions and defend his report is the whole ballgame right now.” The testimony has even found support among Republicans on Capitol Hill, as House G.O.P. lawmakers allied with Trump still signaled their interest in hearing from Mueller. Rep. Doug Collins, the House Judiciary Committee's ranking Republican, echoed his desire to see Mueller testify in a separate interview with Politico, after previously sending a letter to committee chairman Rep. Jerrold Nadler requesting the testimony. “I think Mueller should testify,” Collins said Monday. “There was no collusion, no obstruction, and that's what Bob Mueller will tell everyone.” Republican Judiciary Committee member Rep. Tom McClintock said he also has “a lot of questions” for Mueller and “hope[s]” the testimony will happen. That view doesn't seem to be shared amongst all Republicans; Sen. John Cornyn told reporters Monday “it really would probably be healthy for the country to move on.” Yet even Senate Judiciary chair Sen. Lindsey Graham, who has repeatedly said the Mueller investigation is “over,” is open to some form of Mueller testimony, telling CNN Monday he would agree to public testimony from Mueller specifically on a phone call between him and Barr, which concerned Mueller's letter taking issue with how Barr summarized his report.

Once again, a major flashpoint in the post-Mueller fallout may come down to Barr, who ultimately does have the power to stop Mueller's testimony. The A.G. previously told Congress he does want Mueller to testify, and a source cited by ABC News said his opinion hadn't changed after Trump's tweet. Given that Barr has previously come under fire for shirking his objectivity to defend Trump, of course, it's not inconceivable the A.G. could change his mind or follow an order from Trump to stop Mueller—or that the president could simply risk the legal challenge and block the testimony himself. If he does, though, it's clear this is one presidential opinion where he may not find much support. If Trump blocks Mueller's testimony, “the issue becomes ‘Trump is stonewalling,’ rather than ‘Mueller didn't find anything,’” one Republican aide predicted to Politico. “This will be a bad move.”

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