Connecticut Democrats are working on legislation that would require presidential candidates to release their federal tax returns in order to be included on ballots in the state.

The bill, An Act Concerning Disclosure of Presidential Candidates’ Federal Tax Returns, would force candidates to disclose their federal tax returns for at least the three years immediately before the election. Last week, Democrats used their narrow advantage on the Government Administration and Elections Committee to advance the bill to the House by a 9 to 8 vote along party lines.

The proposed legislation comes as a clear response to President Donald Trump’s refusal to release his tax returns both during the presidential campaign and now. For Democratic Senate President Pro Tempore Martin Looney, the president’s actions have provided ample reason to act.

“I think it raises an important issue about disclosure,” Looney said. “Up until this most recent campaign, candidates had complied with that as a matter of course, and all of a sudden Mr. Trump did not.”

Across the country, 25 state legislatures, most of them controlled by Democrats, have introduced legislation to require presidential and vice presidential candidates to release their federal tax returns. In New Jersey, such a bill has already passed both chambers of the Legislature, although Republican Gov. Chris Christie is expected to veto it.

U.S. Sens. Chris Murphy, D-Conn., and Ron Wyden, D-Ore., have made a similar push at the federal level. First in May and again in January, the two senators introduced legislation that would require presidential candidates of major parties to submit their most recent three years of federal tax returns within 30 days of nomination. The Senate’s Republican leadership ignored the bill on both occasions.

Looney said he does not yet have a sense this early in the session of how likely Connecticut’s version of the bill is to pass.

The issue is split largely along partisan lines. State Republicans have criticized the bill for being too political, suggesting that it is the result of lasting bitterness from the 2016 presidential election.

Looney responded to these accusations by saying that legislation of the sort being considered was not previously necessary because every major party presidential candidate had released their federal tax returns voluntarily since the mid-1970s. Until last year, Looney added, people simply assumed it was a “matter of course.”

However, J.R. Romano, the chairman of the Connecticut Republican Party, said Connecticut Democrats’ focus on the president’s tax returns is an attempt to distract from the more serious economic problems facing the state.

“It’s Democrats [being] more interested in political theater than solving the crisis that is Connecticut’s fiscal cliff,” Romano said. “We’re losing business after business. West Hartford has announced they may lay off 250 teachers. And Democrats in the state are focused on nonsense. I mean, when it comes to prioritizing what’s happening in our country and in our state, they have lost their priorities.”

While Looney is confident in the bill’s importance, he acknowledged that there remains the question of its legality. Some, he said, have suggested it may be “problematic” for states to impose such conditions on national candidates.

In an email to The New York Times about New York’s version of the legislation, though, Harvard constitutional law scholar Laurence Tribe said he does not expect the bill to face any legal stumbling blocks.

“Ballot access requirements vary significantly from state to state, and it seems that [New York] might be able to simply add tax disclosure as a procedural ballot access requirement,” Tribe wrote.

Richard Nixon became the first president to release his tax returns when he did so in 1973.