HELENA — What Montana officials call evidence of corruption that justifies the state’s low campaign contribution limits is really just democracy in action, an attorney for individuals, groups and political organizations trying to strike down the limits said Monday.

Montana is defending its contribution caps, which are among the lowest in the nation, in a federal lawsuit that claims they unconstitutionally restrict freedom of speech, association and candidates’ ability to raise enough money to effectively campaign.

State officials have focused on how Montana is threatened by public officials making promises in exchange for money, after a federal appeals court ruled last year that such quid pro quo corruption, or its appearance, is the only legitimate justification for the caps.

Attorneys for both sides made their arguments Monday before U.S. District Judge Charles Lovell in one of a handful of cases across the nation challenging state contribution limits after the 2010 U.S. Citizens United ruling that allowed unlimited corporate spending in elections. The Citizens United decision raised the standard for states to justify their contribution limits by saying it’s not enough to show they are preventing the influence of big donors over politicians, the 9th U.S. Circuit Court of Appeals ruled.

Under the new standard, states must prove their caps prevent quid pro quo corruption, or its appearance. As evidence, Montana Department of Justice attorneys pointed to an offer by the National Right to Work Committee to donate $100,000 to support Republican legislative campaigns if the lawmakers introduced anti-union legislation. That offer was not accepted.

More recent examples are the state’s cases against nine GOP candidates accused of taking illegal campaign contributions from the National Right to Work Committee in 2010. Earlier this month, a jury found that one of the nine, Rep. Art Wittich, R-Bozeman, took $19,599 in illegal corporate contributions from Right to Work affiliates.

Commissioner of Political Practices Jonathan Motl has said Wittich’s case and the eight others are evidence of corruption, because the candidates pledged fealty to Right to Work’s anti-union cause in exchange for the campaign aid. The jury in Wittich’s trial did not rule on whether Wittich’s acts were corrupt.

James Bopp, the Indiana attorney who has challenged campaign finance laws across the nation, told Lovell Monday that those examples don’t amount to corruption, but democracy. There is nothing wrong with a candidate telling donors that he or she will support a bill that they favor, Bopp said.

In the case of the nine Republican candidates accused by Montana, their “pledge” to Right to Work amounted to filling out a candidate survey that showed they agreed with the anti-union group’s beliefs, he said.

That is not evidence of corruption, Bopp said.

“If that is criminal ... then we have made common, ordinary representative government criminal,” he said.

Wittich and the other cases are examples of serious threats of abuse under the existing campaign laws, Assistant Attorney General Matthew Cochenour said in reply. That proves there is the appearance of corruption, he said.

“Nobody’s saying if you support a candidate, that’s corrupt,” he said.

Lovell said he would consider the arguments, but did not make an immediate ruling. A decision could come before the June 7 primary elections.