Mike Pence just defied Trump. The vice president released a letter on Wednesday afternoon that flatly denied President Trump’s demands that Pence refuse to certify President-elect Joe Biden’s victory. The letter landed like a political bombshell on Wednesday afternoon, moments before Pence was scheduled to oversee the joint session of Congress that will officially seal Biden’s victory. Trump was in the middle of browbeating Pence in front of large crowds from a stage outside the White House just at the moment Pence released the letter. “I do not believe that the Founders of our country intended to invest the Vice President with unilateral authority to decide which electoral votes should be counted during the Joint Session of Congress, and no Vice President in American history has ever asserted such authority,” Pence wrote. The refusal to interfere with certifying the election marks a startling rebuttal from Pence to the president he’s slavishly praised and doted upon for four years, even while staying an arm’s-length away from Trump’s worst scandals. But on Wednesday, faced with a choice between his president and the Constitution, Pence announced he would choose the Constitution. “It is my considered judgement that my oath to support and defend the Constitution constrains me from claiming unilateral authority to determine which electoral votes should be counted and which should not,” Pence wrote, adding that his role overseeing the process is “largely ceremonial.” Pence’s stated view corresponds to the interpretation of almost all constitutional and legal scholars. But Trump vociferously disagrees—and said, repeatedly during Wednesday’s rally, that he’s counting on Pence to refuse certification and find a way to install Trump into a second term. Trump decisively lost the 2020 election but has refused to accept this basic fact, instead casting wild aspersions of fraud that have no basis in reality. “Mike Pence, I hope you’re going to stand up,” Trump thundered from the stage on Wednesday. “And if you’re not, I’m going to be very disappointed in you, I’ll tell you right now. I’m not hearing good stories.” Pence wrote that he welcomed Congress’ role in challenging the electoral vote count—but no mainstream observer thinks Congress will decide to throw out the vote. “Given the controversy surrounding this year’s election, some approach this year’s quadrennial tradition with great expectation, and others with dismissive disdain,” Pence wrote. “Some believe that as Vice President, I should be able to accept or reject electoral votes unilaterally. Others believe that electoral votes should never be challenged in a Joint Session of Congress.” But, Pence continued: “After a careful study of our Constitution, our laws, and our history, I believe neither view is correct.” The move raises questions about how Trump will respond, and whether Pence will be able to maintain the place within Trump’s inner circle he’s spent years cultivating. Pence is widely seen as plotting a run for the presidency in 2024. But Trump has been mercilessly critical of others he views as abandoning him, including the Republican governor of Georgia Brian Kemp and his own former attorney general Jeff Sessions. And there’s little doubt that Pence’s blatant defiance will make Trump frothy with rage. “If Mike Pence does the right thing, we win the election,” Trump told the crowd outside the White House only moments before Pence released his letter. “Has the absolute right to do it.” Trump recently denied a New York Times report stating Pence had already informed Trump he had no power to do what Trump is asking. Now, of course, it appears the Times was right—and Trump was lying, again. “I just spoke to Mike,” Trump told the crowd. “I said, ‘Mike, that doesn’t take courage. What takes courage is to do nothing.’” Trump, however, is wrong. Pence’s role is circumscribed by both the Constitution and federal law.