Minnesota has long been a leader in voter turnout. Now the state has a chance to also be a leader in disclosing which individuals and institutions are behind efforts to influence voters.

Disclosure requirements already exist for campaign ads that directly urge voters to specifically back a candidate — so-called "express advocacy" ads that use campaign phrases like "vote for," "elect," "support," "cast your ballot for," "Smith for Congress," "vote against," "defeat" or "reject."

But in Minnesota, the same rules don't apply to ads that clearly favor a candidate but do so without the types of words or phrases deployed in express-advocacy ads. These ubiquitous messages might urge voters to call a senator's or representative's office and urge her or him to back (or back off) a policy proposal.

Especially when run close to an election, the intent of these ads is quite clear. But who is bankrolling them is not.

That should change. The Legislature should be open to considering new rules if Minnesota's Campaign Finance and Public Disclosure Board advances a proposal to ask lawmakers to require such disclosure for the "functional equivalent" of express advocacy.

Or, as the board states in one of three versions of draft language, "that a communication, when taken as a whole and with limited reference to external events, including the proximity to the election, is not susceptible to any other interpretation by a reasonable person other than that as advocating the election or defeat of one or more clearly identifiable candidates."

Minnesota is replete with reasonable people who know what these ads are intended to do. They just don't know who is paying for them. Requiring disclosure wouldn't mean regulating content or limiting expenditures — the U.S. Supreme Court's Citizens United decision, however controversial, has legally settled that matter.

But the disclosure standards promised by politicians who supported Citizens United need to be applied to these ads.

"The identity of the people behind these messages is a crucial tool in interpreting what they are actually telling you, and what they want from the government," Daniel Weiner, senior counsel with the Brennan Center's Democracy Program, told an editorial writer. "If you don't apply rules to these ads, then they [disclosure rules] are just paper tigers."

Voters deserve disclosure, not paper tigers.

When the state's Campaign Finance and Public Disclosure Board revisits the issue at a Feb. 6 meeting, it should move forward with a request for legislators to take up the matter. Lawmakers in St. Paul should embrace, on a bipartisan basis, disclosure rules that provide Minnesotans with more transparency.

"Voters have a right to know who is spending money to influence their vote on Election Day," Paul Seamus Ryan, vice president of Policy and Litigation at Common Cause, told an editorial writer. "Transparency in elections and government is really important to democracy; a fully informed electorate is critically important to a functioning democracy."

Minnesota voters are among the most engaged and informed in the country. But more knowledge — especially about expenditures meant to influence elections and governance — is needed.