When the Supreme Court irresponsibly overturned a 60-year-old ban on spending by unions and corporations in political campaigns, Congress was faced with a choice.

When the Supreme Court irresponsibly overturned a 60-year-old ban on spending by unions and corporations in political campaigns, Congress was faced with a choice. It could pass legislation purporting to overturn the decision, inviting another invalidation. Or it could work within the confines of the ruling to limit its negative consequences. In general, legislation proposed by Sen. Charles E. Schumer, D-N.Y., and Rep. Chris Van Hollen, D-Md., follows the second course, but it would still strike a blow against special-interest influence in elections.

The title of the DISCLOSE Act — which has been introduced in slightly different versions in the House and Senate — reflects its overriding purpose. That is to inform voters about the sources of advertisements that explicitly or implicitly advocate the election or defeat of a candidate or even mention a candidate during election season.

Disclosure isn't a panacea, but it allows voters to discern, and discount, the agenda behind an ad.

Under the legislation, corporations, labor unions and nonprofit advocacy groups would have to disclose the names of their major contributors. Moreover, their leaders would have to appear on camera to say they "approve this message," as would the primary benefactors of "shell groups" whose names might not reveal their agendas. As President Obama recently put it, the American people "have the right to know when some group like 'Citizens for a Better Future' is actually funded entirely by 'Corporations for Weaker Oversight.'"

Beyond disclosure, the bills would put new restrictions on coordination between candidates and unions or corporations sponsoring advertisements, a perfectly constitutional way to make sure that independent expenditures are just that. Also unassailable on constitutional grounds is a provision barring companies that receive federal bailouts from spending money to influence elections.

Other restrictions sweep so broadly that the Supreme Court might view them as an attempt to repeal its decision through the back door. For example, the legislation would ban independent expenditures by companies with government contracts worth $50,000 or more, and by those in which a foreign national owns 20% or more of the voting shares. Those thresholds are so low that they would affect much of the economy; they should and probably will be raised before final passage. That would still prevent "pay to play" expenditures by defense contractors and other companies that rely mostly on government business.

Overall, the DISCLOSE Act is a robust response to a flawed Supreme Court decision — an overreaching by the court with profoundly negative implications for the role that money plays in our politics — that Congress is powerless to overturn.

The House and Senate should approve it and shine a light on election expenditures by special interests. We suspect that voters often won't like what they see.