Advocates for reducing big money in politics are filing a complaint against super PACs they hope will eventually end up before the Supreme Court. (Marvin Joseph/The Washington Post)

A powerhouse legal team representing a bipartisan group of congressional members and candidates is unleashing a new effort to overturn the case that birthed super PACs, part of a novel strategy to rein in the big money that has poured into campaigns since 2010.

Their immediate target is not Citizens United v. Federal Election Commission, the polarizing decision handed down by the Supreme Court that year. Instead, they are going after a lesser-known case decided by U.S. Court of Appeals for the D.C. Circuit just two months later: SpeechNow.org v. FEC .

That decision, citing Citizens United, permitted a conservative group to raise money beyond the contribution limits placed on traditional PACs because it planned to spend its funds independently of a candidate or party. In doing so, the appellate court paved the way for new political vehicles — later dubbed super PACs for their ability to accept unlimited amounts from individuals and corporations.

A team of attorneys including Laurence Tribe, a professor of constitutional law at Harvard University, and Richard Painter, who was the chief ethics lawyer for former president George W. Bush, are taking aim at SpeechNow.org with a new complaint they hope will reach the Supreme Court before the 2020 elections.

The thrust of their argument: The lower court erred in its interpretation of a line in the Citizens United decision, a mistake that unleashed a flood of money into elections that the Supreme Court never intended.

“The situation left in place by SpeechNow.org is one that Congress never enacted and people would never support,” Tribe said. “The law permits a very severe limit on the amount an individual can give to someone’s campaign, but at the same time that could be evaded by giving millions to super PACs. . . . The Supreme Court never approved anything like that.”

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On Thursday morning, the team is filing a complaint with the Federal Election Commission on behalf of six members of Congress and congressional candidates against 10 super PACs. The effort cites groups across the political spectrum, including the Democratic House Majority PAC and the Republican Congressional Leadership Fund.

“People feel like the system they grew up with that gave a substantially proportional voice to each citizen has been replaced by a stadium sound system drowning out voices of the citizens,” said Sen. Jeff Merkley (D-Ore.), one of the lawmakers who is part of the challenge. “It tremendously feeds their cynicism.”

The other complainants are Rep. Ted Lieu (D-Calif.); Rep. Walter B. Jones (R-N.C.); John Howe, a GOP candidate in Minnesota; Zephyr Teachout, a Democrat running in New York; Michael Wager, a Democratic candidate in Ohio; Free Speech for People, a nonprofit legal advocacy group; and the nonpartisan Campaign for Accountability.

The group is asking the FEC to investigate the super PACs for violating election law by accepting contributions larger than the $5,000 donation limit to traditional PACs. The complaint argues that the agency is not bound by the D.C. Circuit’s ruling in SpeechNow.org.

If the commission declines to investigate, the team plans to file a lawsuit in federal court that it hopes will get considered by the Supreme Court.

Lead attorney Ron Fein, the legal director at Free Speech for People, said he believes their argument is one that “even a justice that joined the Citizens United decision” would support.

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But conservative election law attorney James Bopp Jr., who has successfully led efforts to roll back campaign finance restrictions, dismissed the complaint as “a case going nowhere.”

“There would have to be a radical change on the [Supreme] Court for them to go another direction,” said Bopp, adding that half a dozen federal appellate courts have held that contribution limits cannot be placed on groups doing independent spending.

The SpeechNow.org case, which was argued just six days after the Citizens United decision was handed down, leans on Justice Anthony Kennedy’s assertion in the opinion that money spent independently of a candidate or party does not “give rise to corruption or the appearance of corruption.”

Citing that, the D.C. appellate court ruled that contributions to groups that only make independent expenditures cannot corrupt, and thus cannot be limited. That was a mistake, Fein maintains, saying that court erroneously treated contributions like expenditures.

Bopp disagrees. “Once you break the connection between the candidate and the money, well, you no longer have the prospect of corruption,” he said.

But the SpeechNow.org challengers argue that notion has been undermined by the developments of the last six years. Super PACs are now the norm in competitive federal races, with many formed to back a single candidate, run by that candidate’s longtime aides or associates and financed by their family and friends.

“Nobody, nobody who is operating in the real world is confident that there exists this kind of impenetrable wall of independence,” said Norm Eisen, a former ethics czar in the Obama administration and ambassador to the Czech Republic, who is serving as a counsel on the case.

“The assumptions that underlie both the Citizens United case and the SpeechNow case have been proven to be dramatically wrong over the course of the past six years,” Eisen added, “and it’s a hallmark of American jurisprudence that when the facts change, opinions change.”