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If President Trump's newly diagnosed COVID-19 infection progresses to the point where he is incapacitated, "the Constitution's 25th Amendment spells out the procedures under which" he could hand his "powers and duties" to Vice President Mike Pence by sending "a written note to the Senate president pro tempore, Republican Sen. Chuck Grassley of Iowa, and House Speaker Nancy Pelosi (D-Calif.)", The Associated Press reports. "Pence would serve as acting president until Trump transmitted 'a written declaration to the contrary.'"

But what happens if the virus spreads to Pence and he becomes incapacitated at the same time? "We could face a constitutional crisis," University of Texas law professor Sanford Levinson explained in The Washington Post back in May, after British Prime Minister Boris Johnson had to temporarily hand off power while battling COVID-19 in the ICU. The 1947 Presidential Succession Act would, at least in theory, hand the presidency to Pelosi, then Grassley, and finally members of Trump's cabinet, beginning with the secretary of state, Levinson wrote.

But Pelosi is a Democrat, and "any effort to transfer power from Trump and Pence to Pelosi would surely inspire legal and political challenges, adding to chaos at precisely the moment the nation desperately needed stability," Levinson wrote, and there are open questions about whether the Presidential Succession Act is even constitutional, whether Pelosi would have to resign as speaker for her short stint as president, and whether the Supreme Court would step in. When Levinson made his argument, Justice Ruth Bader Ginsburg was alive; now Trump is likely to push another conservative onto the court before or right after the election.

"Just as the United States turns out to have been woefully unprepared to confront the coronavirus, so are we unprepared to confront simultaneous presidential and vice-presidential disability," Levinson concludes. Read his timely analysis at The Washington Post.