A court has rightly upheld a Minnesota law that requires corporations to disclose when they spend money to support or defeat a political candidate.

The law requires reports on corporate spending for or against candidates. The law requires two reports to be filed before the primary and two more before the general election. The law also applies to groups supported by unions. Requiring those disclosures is allowed by federal law, the Eighth U.S. Circuit Court of Appeals said Monday.

In addition, a Minnesota corporation may donate its own money to an existing independent expenditure committee or fund without providing any information beyond its name and address. If the business solicits and receives contributions beyond its general treasury revenue, it must disclose the source of the contributions.

The appeals court got involved because the U.S. Supreme Court ruled last year that bans on “independent” expenditures were an infringement on free speech. But the court also said states could require disclosure of such spending. As a result, the Minnesota Legislature amended the law to require disclosure.

The Minnesota Citizens Concerned for Life, the Taxpayers League of Minnesota and Coastal Travel Enterprises argue that Minnesota’s law hampers their right to free speech by improperly limiting corporate support for candidates and causes.

But what harm can come from knowing where the money comes from that supports or helps defeat a candidate? If a corporation feels strongly enough to throw its money behind or at a candidate, shouldn’t voters know a little background on that activity?

The court’s action reiterates that Minnesota’s law is appropriate to help inform the public about which special interests are attempting to influence voters as they elect candidates for public office.