Last week, the 4th Circuit Court of Appeals affirmed the constitutionality of a federal law making it illegal for corporations to make direct contributions to political candidates. The decision was a rare bit of good news for campaign finance reformers, whose hopes that the Supreme Court would reconsider giving a green light to indirect corporate campaign spending in Citizens United v. Federal Election Commission were dashed when the justices struck down a Montana law that restricted corporate political expenditures.

The 4th Circuit case -- which involves criminal charges against two supporters of Hillary Clinton's who have been accused of funneling $186,000 in corporate funds to her 2006 Senate race and 2008 presidential campaign -- may be the next corporate campaign finance challenge to reach the Supreme Court.

If it does, research by two academics who have studied the effect of corporate contributions on the public's perception of government could play a significant role in the outcome. In its opening brief at the 4th Circuit in the prosecution of William Danielczyk and Eugene Biagi, the government cited research to support its conclusion that corporate contributions "heighten public perceptions that government is corrupt." But the authors of the research, political science professor David Primo of the University of Rochester and economics professor Jeffrey Milyo of the University of Missouri at Columbia, disagree. In a brief of their own, they argued the evidence shows that "campaign finance laws have little to no effect on public perceptions of government."

It's not an academic point. To uphold the ban on direct contributions by corporations, courts historically have relied on the government's interest in preventing actual and perceived corruption. But in an interview with Reuters, Primo said that those justifications can no longer hold up to scrutiny. Corporations can already give to campaigns through political action committees, he said, which makes it harder to justify the ban on direct contributions as a way to prevent the perception of corruption.

"That just doesn't hold water," Primo said.

He added that there's scant evidence to show that allowing a corporation to give directly to federal candidates under the same limits imposed on individuals would increase actual corruption.

"I think it's possible that the Supreme Court could use the Danielczyk case as an opportunity to weigh in the legality of that ban," said Primo. "I think that's what makes the case so powerful."

(Reporting by Andrew Longstreth)

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