J. Michael Luttig is a retired judge of the U.S. Court of Appeals and a prominent legal mind in conservative circles, close with figures including Clarence Thomas and William Barr. On January 5, 2020, he got a call from Vice-President Mike Pence’s then-lawyer asking Luttig to publicly back Pence’s decision not to attempt to overturn the election the next day. Luttig tweeted that the Vice-President had no constitutional authority to stop the election, and suddenly the judge was thrust into the center of the crisis.

Now Luttig is siding with Democrats as co-counsel on the Supreme Court case Moore v. Harper, which he tells David Remnick is “the most important case, since the founding, for American democracy.” At the heart of the debate is the independent-state-legislature theory, a once-fringe legal concept that Donald Trump and his allies believe should have allowed Pence to reject the popular vote in 2020. If the court adopts the theory, it could grant legislatures essentially unfettered authority to run national elections; they could not be challenged even if the election violated the state constitution. Such power, in the hands of a gerrymandered legislature, could be used to bypass the popular vote and appoint a new slate of electors, effectively empowering state lawmakers to choose a winner. The court will hear the case on December 7th.