President Trump listens during a meeting March 19 with Brazilian President Jair Bolsonaro in the Oval Office. (Kevin Lamarque/Reuters)

In refusing to release his tax returns, President Trump bucked decades of tradition and set off a Democrat hunt to obtain them. Now several statehouses are looking at making their release a condition of the 2020 presidential election: Show us your tax returns, or you can’t be on the ballot.

Eighteen states have considered legislation this year that would require presidential and vice presidential candidates to post their tax returns to appear on the ballot during a primary or general election, according to data from the National Conference of State Legislatures (NCSL).

Proponents of the bills, such as the one passed by the Washington state Senate this week, say they are aimed at increasing transparency and returning to the “norm” of candidates releasing their financial records. But Democratic lawmakers behind the some of the legislation have admitted they are also very much about Trump, which raises legal and political questions about how far states can — or should — go in regulating who appears on their ballot, especially in a hyperpartisan climate.

Trump has long insisted that he won’t release his returns because they are under audit, though that would not preclude him from doing so. The documents have become something of a liberal white whale, and Democrats at the federal level have been pursuing laws or legal maneuvers aimed at obtaining them.

In addition to Washington, several other states, including California, Hawaii and New Jersey are considering similar bills. Many, though not all, of the legislatures considering the bills are controlled by Democrats, but even in Republican-controlled states, Democrats have put forth such legislation. Measures failed earlier this year in Mississippi, New Mexico and New Hampshire.

“It is so obvious with this president that had voters known some of what seem to be his business interests, he may not have been elected president,” New Jersey state Sen. Loretta Weinberg (D), a co-sponsor of the bill approved by the state senate last month, told the Courier-Post.

Similar attempts have been made by states since Trump was elected. In 2017, Dan Diorio, policy specialist in NCSL, noted that at least 25 state legislatures put forward such bills. “Nearly every bill has been introduced by Democrats, in reaction to President Donald Trump’s refusal to release his tax returns as per the custom of previous presidential candidates,” he wrote of the 2017 legislation.

While Democrats appear to be driving these bills, Dan Weiner, a senior counsel for the Brennan Center for Justice’s Democracy Program, told The Washington Post that there was bipartisan support more generally for increasing transparency around presidential candidates’ finances.

“It is always true in American politics that these ideas are championed by perhaps the side that has more of political grievance at that particular moment,” Weiner said. “That doesn’t mean it’s not a good idea.”

However, Weiner said it would be more helpful for a uniform federal law that dictates disclosures, rather than having individual states pass laws with different or conflicting requirements of candidates.

And not all politicians think this kind of legislation is a good idea. In 2017, then-New Jersey Gov. Chris Christie vetoed one bill that made it to his desk, calling it “politics at its worst.” Former California governor Jerry Brown, a Democrat, did the same when California’s legislature passed similar measure.

“First, it may not be constitutional,” Brown wrote in his decision. “Second, it sets a ‘slippery slope’ precedent. Today we require tax returns, but what would be next? Five years of health records? A certified birth certificate? High school report cards? And will these requirements vary depending on which political party is in power?”

In 2019, both states have new governors, and their legislatures are once again considering bills that will force candidates to release tax returns if they want to appear on a ballot.

States have the right to set requirements for candidates to appear their ballot, such as obtaining a certain number of signatures or abiding by campaign finance rules. But whether they can demand tax returns from a presidential candidate remains legally untested.

Richard L. Hasen, an election-law expert, considered the legality and prudence of these measures in Politico Magazine. While Hasen argues that cases for and against constitutionality could be made, Democrats might be opening a “Pandora’s box” by pursuing it.

“Will solidly Republican states allow electors to vote only for Republican candidates for president?” he wrote. “If the tax gambit is OK, then such a law might also be constitutional. Or perhaps the GOP would retaliate with laws aimed at voter suppression or other such measures that target typically Democratic constituencies."

Plus, Hasen writes, “no doubt as soon as they are enacted, such laws would be challenged in court. Trump would already have standing to challenge, as he declared his candidacy for reelection in 2020 on the day he was inaugurated. There’s plenty of time for courts, even the Supreme Court, to work out the issue before 2020 ballots would have to be printed in any state.”

Demanding tax returns is not the only gambit that states have pursued to remedy perceived flaws in the democratic process. In recent years, some states have voted to restore voting rights to certain formerly incarcerated individuals or to establish independent commissions to draw congressional districts in an attempt to crack down on gerrymandering.

When Sen. Elizabeth Warren (D-Mass.), a Democratic presidential candidate, called for the abolition of the electoral college this week, she put a spotlight on several states’ efforts to reform that system. Twelve states and the District of Columbia have signed on to the National Popular Vote Interstate Compact, in which states pledge to give their electoral votes to the winner of the popular vote. However, not enough states have signed on for it to have an impact on the 2020 presidential election.

“I think one of the things we’re seeing is the resurgence in the general public’s interest in democracy reform,” said Rudy Mehrbani, a colleague of Weiner’s at the Brennan Center. “I think this goes hand in hand with other efforts around empowering voters, increasing access to the ballot, and making sure that democracy is more responsive to constituents generally.”

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