It’s been three years since the Supreme Court’s Citizens United decision and the American political system is, for better or worse, still standing. To be sure, the landmark ruling paved the way for millions of corporate dollars to be spent during the 2012 election cycle on independent expenditure campaigns. But the ultimate impact of Citizens United— whether that money can truly sway an election—remains unclear.

As we head into the next cycle, numerous other campaign finance laws remain in place and, in many instances, ripe for legal challenges. And nowhere is this more important than at the U.S. Supreme Court.

Since Citizens United, justices have taken a much more nuanced view of campaign finance laws than the apocalyptic headlines following its landmark 2010 decision would suggest. The court upheld a ban on unlimited contributions to national political parties in Republican National Committee v. Federal Election Commission. It also left in place Connecticut’s public financing law for state elections.  Most recently, the court declined to weigh in on a case challenging corporate contributions directly to candidates, Danielczyk v. United States, which many observers viewed as the next logical step in campaign finance deregulation after Citizens United.

Those developments show a Supreme Court still grappling with the many aspects of campaign finance laws, says Justin Levitt, an election law expert at Loyola Law School in Los Angeles.

“The conventional wisdom is that Citizens United meant the end of all campaign finance regulation,” he says. “But it’s really only an over-emphatic answer to one question. And it doesn’t tell you how the court views different questions.”

Legal observers note the court seems to remain concerned about the appearance of corruption, the quid pro quo involving a symbolic suitcase full of cash passed from a single donor to an elected official. That was a key holding in the landmark 1976 Buckley v. Valeo ruling and the court has historically granted states and Congress deference in setting campaign contribution limits for that reason. But some experts see problems in Buckley’s reasoning.

Michael McConnell, a professor at Stanford Law School and former federal circuit judge, says Buckley has a “central incoherency” that was made apparent in the last election, when Super PACs and other independent groups blanketed the airwaves. The ruling, he says, draws a distinction between contributions, which could be limited, and independent expenditures, which, as Citizens United showed, should not.

“The court asserts, with no evidence and contrary to the views of almost everyone familiar with the issue, that the former have the potential for corruption and the latter do not.”

Since Buckley, federal limits on contributions directly to candidates have been unimpeachable at the court—the justices have never struck one down. That may change next fall, however, when the court will consider a case from an Alabama businessman and the Republican National Committee.

Aggregate limits in question

Shaun McCutcheon is a frequent contributor to Republican candidates, PACs and the Republican National Committee. In the process of cutting checks last cycle, he ran into the FEC’s aggregate limits. So while he didn’t want to exceed individual limits of $2,500 to a candidate per election, $30,800 to a national party per year and $10,000 to other political committees per year, when he added up all his donations, he exceeded the aggregate limit of $46,200 to candidates and $70,800 to all other committees. McCutcheon wanted his contributions to candidates to top the individual limit by about $8,000 and the limit to parties and PACs by just over $26,000.

At first blush, the challenge seems to make logical sense. McCutcheon isn’t giving any one candidate a suitcase full of cash. He’s abiding by the federal contribution limits. But the case has caught the eye of election law experts because it could open the door to contribution limits more generally.

“The issue that is lurking is whether or not this becomes a springboard to further challenges to contribution limits,” says Richard Briffault of Columbia Law School. McCutcheon’s lawyer, Indiana’s James Bopp, hopes the justices take a dive of that springboard.

“It provides the opportunity for the court, if it wants to, to opine and even re-examine how they treat contribution limits,” says Bopp, who also worked on the Citizens United case. “We will certainly be providing a basis for the court to do that if they want to.”

Bopp argues that contribution limits need re-examining in the post Citizens United world. The unlimited cash flowing through independent expenditures is drowning out the candidates’ campaigns, he says, noting that several states have recently raised contribution limits.

“Politicians need to start reevaluating how contribution limits are making them bit players in their own elections,” he says.

Other legal experts note that the suitcase full of cash still exists in the McCutcheon case, just not as obviously. While the money doesn’t go directly to a candidate, there is little to stop a party or a PAC from funneling it to the donor’s candidate of choice or spending it on ads on his or her behalf.

Fred Wertheimer, a campaign finance reform advocate with Democracy 21, thinks the case could eviscerate a key provision of campaign finance law: a prohibition on candidates soliciting huge sums of money from individual candidates.

President Obama’s fundraisers during his last campaign often had ticket prices of up to $50,000, which was then divided up among his campaign and Democratic committees. If the aggregate limit is lifted, Wertheimer says, those tickets could go for $1 million or more. In that instance, the suitcase full of cash is very real.

“That money could end up being spent for the individual who solicited it,” Wertheimer says. “Regardless of how the money is divided up, you would have an official soliciting $1 million checks which is a clear formula for corruption.”

Chris Shays, the former Republican congressman and Senate candidate from Connecticut, offered another solution. The current spending levels between independent groups and candidate campaigns are so out of whack that Congress should step in.

“I don’t think the court should overrule it,” says Shays, a leading voice on campaign finance reform, “but I think Congress should look at whether that amount should be doubled or tripled.”

What’s next?

The court has also put on hold whether it will consider another case involving aggregate limits. James v. FEC challenges the commission’s cumulative limit on contributions to individual candidates only. The suitcase still exists there, as well. In theory, a contributor could give money to every senator and each senator could, in turn, give that money to the donor’s preferred candidate.

Legal experts also noted that campaign coordination is becoming ripe for challenges. When a Republican presidential nominee talks about his Super PAC, it raises questions about whether the PAC is independent. Is a contribution to his PAC, then, really an independent expenditure? Or is it a contribution to the candidate? Wertheimer notes the separation between PACs and candidate campaigns was a building block of the Citizens United decision.

“Efforts are going to be made to get real coordination rules,” he says. “Right now, the lynchpin of Citizens United is based on the idea that expenditures must be independent. That’s just a joke today.”

Another issue that has risen to the Supreme Court level previously centers on the duty of a publicly-elected judge to recuse themself from cases involving citizens who spent money on their behalf. In 2009, the court ruled in Caperton v. A.T. Massey Coal Co. that a judge must recuse himself if there is a situation that creates a probability of bias. In that case, a West Virginia Supreme Court of Appeals judge ruled in favor of a mining company whose CEO spent millions of dollars on independent expenditure ads during the judge’s last campaign.

The ruling left plenty of questions unanswered, including just what threatens the judicial branches’ impartiality. How much money is too much?

Bopp, the Indiana lawyer, says it’s hard to predict what the court will take up. But Bopp seems to know better than most: The McCutcheon case represents his seventh case before the justices. And he isn’t showing any sign of slowing down.

“It’s just really unpredictable which ones the court ultimately finds suitable for its agenda,” he says. “You just present them with as many worthy cases as you can.”

Jeremy P. Jacobs covers the Supreme Court for Greenwire, a publication of Environment and Energy Publishing, LLC.