California could become the first state in the country to require presidential candidates to release their tax returns before gaining a spot on the primary ballot.

The new legislation takes aim at Donald Trump, the first president in 40 years to refuse to release returns. The only other major-party presidential nominee not to release returns was Gerald Ford in 1976. Gov. Gavin Newsom has until Tuesday to sign or veto the bill.

While the Democratic governor has been vocal with his criticism of the president's unwillingness to release the returns, Newsom said on Wednesday that he was still considering the legal implications of the bill. His predecessor, Jerry Brown, vetoed similar legislation in 2017, citing constitutionality concerns and the “political perils” of setting a “slippery slope” precedent that could enable either party to change requirements based on ideology.

California legislators are hoping for a different outcome this time.

“Now we have a different governor,” said Sen. Scott Wiener, a Democrat representing San Francisco who co-authored both bills with Sen. Mike McGuire, who represents a coastal region stretching north of San Francisco. “We want to give him the opportunity to weigh in, and hopefully he will sign it.”

Wiener said he believes the bill is legal, taking the position that the new requirement doesn’t create new qualifications for the office (which are outlined in the U.S. Constitution), but is more administrative.

California’s Democratic legislators aren’t alone in wanting the returns to be revealed. A 2018 Quinnipiac University poll found that roughly two-thirds of voters across the nation want to see Trump’s taxes made public.

According to the National Conference of State Legislatures, seven other states— Illinois, New Jersey, New York, North Carolina, Oregon, Pennsylvania and Rhode Island — are considering new tax return disclosure requirements. Four more — Hawaii, Minnesota, Vermont and Washington — have new legislation scheduled for upcoming sessions. California is the closest to enacting the legislation, a move that could embolden other states to follow.

New York Gov. Andrew Cuomo, a Democrat, in June signed a bill to allow Congress to access Trump’s state tax returns. The measure requires the state to release the president’s state tax returns — along with the returns for certain other federal officeholders — for any legitimate purpose upon request from the House Ways and Means Committee, the Senate Finance Committee or the Joint Committee on Taxation.

If Trump’s battle with Democrats on Capitol Hill is any indication, it’s clear the president would resist any efforts by California to compel him to release his tax returns.

Congress has failed to get the financial documents from the IRS, which was given direction from the U.S. Treasury Department not to hand them over, despite an official subpoena from the House Ways and Means Committee. In May, Treasury Secretary Steven Mnuchin defied precedent and refused to comply with the request, arguing that Congress had no "legitimate legislative purpose" to request the returns.

Earlier this month, the committee sued both the IRS and the Treasury Department for not complying and has now petitioned the state of New York, where the president filed his returns. Trump responded this week with a lawsuit, hoping federal judges will issue him a temporary restraining order while he seeks to challenge the New York state law.

Sen. Wiener says thatif SB 27 is enacted, he anticipates there be push-back.

“We are reasonably confident someone will file a lawsuit to challenge it,” he said. “But that’s their right, and that’s why the courts are there.”

The California Republican Party, which advocates for the roughly 5 million registered Republicans in the state of 40 million, has rebuked the bill, calling it “clearly unconstitutional” and is pushing for a veto.

“The Constitution clearly lists the requirements for the Presidency — and the release of tax returns is not one of them,” Party Chairwoman Jessica Patterson said in a statement. “I urge Governor Gavin Newsom to veto this unconstitutional bill, and I encourage Democrats in the Legislature to drop the political posturing and focus on addressing the myriad of problems truly impacting Californians, including the skyrocketing cost of living or our failing education system.”

Even so, Wiener said the California legislation is about more than just taking on the Trump Administration, and hopes the bill will help highlight the importance of requiring financial disclosures from top officials.

“It is about all candidates, current and future,” he said, emphasizing that he thinks most of the electorate assumed until now that the decades-long tradition of making financial statements public when seeking the presidency was actually a requirement.

“Donald Trump just happened to be the one who brought this issue to the forefront and alerted people that something needed to be done to close this loophole,” he added.

“This is about transparency and the American people having confidence that the leader of our country doesn't have deep financial conflicts. He is the most powerful person in the world that has the ability to massively impact national and international society — and we want to make sure that we have full information about this person’s financial affairs.”

California oil issues:After tour of massive oil spill, Gov. Newsom calls for answers; critics quick to finger new, lax regulations

Trump administration and immigration:Supreme Court allows border wall spending in battle between President Donald Trump and liberal opponents

Gabrielle Canon is USA Today's California reporter based out of Sacramento. Contact her at gcanon@gannett.com.