President Donald Trump and the Republican National Committee have filed suit against California over a law that requires presidential candidates to release their tax returns in order to appear on the state’s primary ballot, one of Trump’s personal lawyers said Tuesday,

“Today we have taken decisive action in federal court challenging California’s attempt to circumvent the U.S. Constitution,” Jay Sekulow, a member of Trump’s personal legal team, said in a statement. “The issue of whether the President should release his federal tax returns was litigated in the 2016 election and the American people spoke. The effort to deny California voters the opportunity to cast a ballot for President Trump in 2020 will clearly fail.”

“Legal scholars from across the political spectrum have roundly condemned this flagrantly illegal statute. We are confident the courts will as well,” Sekulow added.

Last month, California Gov. Gavin Newsom, a Democrat, signed a law that requires presidential candidates to submit tax returns for the most recent five years to California’s secretary of state in order to appear on the state’s primary election ballot. Under the law, candidates must submit the returns at least 98 days before the primary. The filings will then be posted online for the public to view, with certain personal information redacted. The law does not apply to the general election ballot.

California’s primary in 2020 in scheduled for March 3, on what is known as “Super Tuesday.”

RNC Chairwoman Ronna McDaniel, in a statement, called the law a “stunt by Democrats” that is “unconstitutional, and simply put, desperate.”

“It certainly doesn’t bode well for Democrats heading into 2020 that their best bet for beating President Trump is to deny millions of Californians the ability to vote for him,” she said.

In a tweet, Newsom urged Trump to “release your tax turns as you promised during the campaign and follow the precedent of every president since 1973.”

While the law would apply to all presidential contenders and candidates for governor, it is aimed at Trump, who has broken years of precedent in refusing to release his tax returns.

Even if the law withstands Trump’s legal challenge, however, the president could still avoid the requirements by choosing not to compete in California’s primary. With no credible GOP challenger at this point, he likely won’t need California’s delegates to win the Republican nomination.