I have written this piece for Politico. A snippet:

Now, though, a band of state lawmakers is attempting to succeed where so many others have failed. In at least 24 states, legislators have introduced bills that would force Trump (and all other presidential candidates) to disclose their tax returns in order to qualify for their states’ ballots in 2020.

There’s one big obstacle, though: Requiring presidential candidates to release their taxes as a condition of ballot access may not be constitutional. And even if it is, the Democrats sponsoring such legislation run the risk of major retaliatory measures being taken in Republican states…..

The idea of using ballot access to force politicians to do something they don’t want to do is not new—nor is the fight over the move’s constitutionality. The Supreme Court’s 1995 ruling in U.S. Term Limits v. Thornton held that Arkansas could not deny ballot access to congressional candidates who had served more than three terms or to Senate candidates who served more than two terms—measures the state had enacted to create congressional term limits. The Court held that the Constitution set the exclusive qualifications for running for federal office (including age and citizenship requirements), and that allowing individual states to impose addition qualifications “would erode the structure designed by the Framers to form a ‘more perfect Union.’” So while states can set reasonable conditions for presidential candidates to get on the ballot, such as requiring a certain number of petition signatures to be listed, they cannot go further and set substantive conditions for who can run.

In light of such precedent, what could possibly be the basis for upholding a state law barring ballot access for presidential candidates who decline to release their tax returns? After all, Article II of the Constitution includes exclusive qualifications for the office of the president: The president must be a natural-born citizen who is at least 35 years old and has resided in the United States for at least 14 years.

The answer lies in another part of Article II—the part that received some important attention in Bush v. Gore, the Supreme Court decision that Democrats love to hate. Famously, the 2000 case between Republican nominee George W. Bush and Democratic nominee Al Gore effectively handed the election to Bush when it ended the Florida recount….