Sheets of one hundred dollar bills sit in a roll before being sorted at the Bureau of Engraving and Printing in Washington, D.C., U.S., on Wednesday, Oct. 14, 2009. (Andrew Harrer/BLOOMBERG)

The Supreme Court’s decision in Citizens United v. Federal Election Commission rearranged the political landscape. And fallout from the decision continues to reverberate in courts across the nation.

The court’s January 2010 decision freeing corporations and unions to spend whatever they like for and against candidates wiped out laws in 24 states banning such spending. Only Montana still wages a lonely court battle to maintain the ban.

But the fight goes on over questions still remaining from the court’s controversial 5 to 4 decision. Issues such as how the government may regulate disclosure of spending, and whether bans on direct corporate contributions to candidates are compatible with the court’s reasoning in Citizens United, are being litigated from one coast to the other.

James Bopp, the Republican activist and anti-campaign-regulation crusader who brought the original Citizens United case, estimates he and his associates are involved in 25 to 30 cases around the country.

He suffered a defeat in the latest federal appeals court to weigh in on the issue. A three-judge panel of the U.S. Court of Appeals for the 8th Circuit refused to stop Minnesota’s law on corporate disclosure of campaign spending, saying it was unlikely to violate free-speech rights.

But one dissenting judge said the law did not conform with the Citizens United decision, and Bopp plans to ask the entire circuit to hear the issue. The next stop after that would be the U.S. Supreme Court.

Tara Malloy, associate legal counsel of the pro-campaign-regulation Campaign Legal Center, said Minnesota’s law is important because it could serve as a model for federal disclosure legislation.

The challenge, she said, could help resolve “what the parameters of disclosure are going to be in the post Citizens United era.”

The law requires corporations and independent expenditure groups to submit several reports in election years and requires disclosure of large expenditures within 24 hours in periods near elections.

Bopp asked for an injunction against the law, enacted after the Citizens United decision, but a district judge and the appellate panel declined. “The burden on corporations appears light,” wrote Circuit Judge Michael J. Melloy, adding that the law meets a legitimate government interest because it “greatly enhances the transparency of corporate expenditures while imposing only reasonable burdens.”

Dissenting Chief Judge William Jay Riley disagreed: “Under Minnesota’s scheme, a corporation is compelled to decide whether exercising its constitutional right is worth the time and expense of entering a long-term or even perpetual morass of regulatory red tape. Some corporations will decide the exercise is simply not worth the trouble.”

Riley joined the rest of the panel in upholding another part of the law that was challenged by a Minnesota company and two interest groups: a ban on direct corporate contributions to candidates.

The Supreme Court upheld such a ban in a 2003 decision, Federal Election Commission v. Beaumont . The justices did not address the issue in Citizens United, but Riley said the court’s reasoning leaves Beaumont’s precedential value “on shaky ground.”

But Riley said it was not up to appellate courts to overturn Supreme Court precedents.

The ban is being tested in other places as well; the U.S. Court of Appeals for the 9th Circuit is considering the city of San Diego’s law. “We don’t expect lower courts to overturn Supreme Court decisions,” Bopp said, “but you do have to raise these issues” in hopes of getting the subject before the high court again.

The court has not seemed particularly eager to again dive into tests of the McCain-Feingold campaign finance reform act, a part of which was overturned in the Citizens United decision. It turned down Bopp’s petition to reexamine the ban on “soft money” to political parties.

But other challenges are underway. A federal district court in Washington earlier this month heard a challenge from a foreign-born lawyer and doctor on the ban against foreign nationals working in this country to contribute to candidates.

If the court accepts more election-law cases, it is likely to be because conservative activists such as Bopp present it with the opportunities, according to one expert in the field.

Richard Hasen, who teaches at the University of California at Irvine School of Law and is helping defend San Diego’s statute, notes what he calls a dramatic drop in election law cases appealed to the high court.

The most likely reason, he concluded, is that liberal litigants who once sought court review are wary of a divided court swung the other way when Justice Samuel A. Alito Jr. succeeded Justice Sandra Day O’Connor.

“If that’s the case,” Hasen wrote in an article last month, “the number of election law cases heard by the Supreme Court should remain low, unless conservative litigants bring more suits to reverse or cabin earlier, more liberal election law precedents.”