The New Jersey legislature listen as assemblyman John McKeon, D-Madison, speaks about a bill requiring presidential candidates to disclose tax returns in order to appear on ballots in the state during a meeting in the state legislature, Thursday, March 16, 2017, in Trenton, N.J. The measure, which was approved by the assembly, requires presidential and vice presidential candidates to release five years of federal tax returns to appear on the ballot. The bill will head to Republican Gov. Chris Christie to sign or veto. (AP Photo/Julio Cortez)
The New Jersey legislature listen as assemblyman John McKeon, D-Madison, speaks about a bill requiring presidential candidates to disclose tax returns in order to appear on ballots in the state during a meeting in the state legislature, Thursday, March 16, 2017, in Trenton, N.J. The measure, which was approved by the assembly, requires presidential and vice presidential candidates to release five years of federal tax returns to appear on the ballot. The bill will head to Republican Gov. Chris Christie to sign or veto. (AP Photo/Julio Cortez) Credit: Julio Cortez

HONOLULU — Lawmakers in nearly half the states want to add a requirement for presidential candidates: Show us your tax returns.

The issue has dogged President Donald Trump, who became the first presidential candidate in modern times to refuse to make his returns public. It flared anew this week after MSNBC said it had obtained two pages of Trump’s 2005 federal return, prompting the administration to release the documents preemptively.

State lawmakers around the country, mostly Democrats, want to ensure transparency in future presidential campaigns so voters can evaluate candidates’ sources of income and any possible conflicts of interest. Most of the bills would require presidential contenders to release copies of their returns as a condition for appearing on that state’s ballot, although it’s unclear whether they could pass constitutional muster.

The aim is to find out about potential conflicts that candidates might have before they take office, said Hawaii Rep. Chris Lee, a Democrat who introduced one of the Hawaii bills.

“With what we’ve seen so far with this administration, there are clear conflicts with respect to whether or not parts of the president’s business empire are directly benefiting from federal contracts to house Secret Service at his own hotels, for example, or pressuring foreign dignitaries or other corporations indirectly to patronize the businesses that the president or his children run,” Lee said.

Trump has refused to make his tax returns public, breaking a decades-long tradition among presidential candidates. He initially promised to do so but then claimed he was under audit by the Internal Revenue Service and said his attorneys had advised against it. Experts and IRS officials said such audits do not prohibit taxpayers from releasing their own returns.