The Supreme Court has given campaign finance laws a beating over the last few years, but a few key restrictions are still intact—to conservatives’ apparent chagrin. In the wake of last week’s ruling striking down limits on overall donations to federal candidates, RNC Chairman Reince Priebus said yesterday that he’d like to see donation limits to individual candidates disappear too. “I don’t think we should have caps at all,” Priebus told talk radio’s Hugh Hewitt. So far, the Court has stopped short of that point. But what has it wrought in the meantime?

With even more money flooding into politics, it’s intuitive to expect more corruption as well. But the Court can’t agree on that proposition. In fact, it can’t even agree on what “corruption” means. Chief Justice Roberts argues that campaign finance laws are justified only if they target “corruption” in the form of quid pro quo deals (or the appearance thereof). The Court’s liberals, led by Justice Breyer, disagree: As Breyer wrote in his dissent, “the plurality defines ‘corruption” too narrowly”—something akin, he noted, to an outright bribe. But “the anticorruption interest that drives Congress,” Breyer claims, is “broader” and “more important […] It is an interest in maintaining the integrity of our public governmental institutions.”

This argument makes Roberts’s narrower definition look positively obtuse, but it has proved troublesome for researchers who study the effects of political donations. It’s one thing to match bribe-taking politicians to donor records, but how do you measure concepts like “influence” and “integrity,” or get around the basic problem that donations may correlate with votes simply because donors contribute to like-minded politicians?

Fortunately, new research by Joshua Kalla and David Broockman has shed light on this question. Kalla and Broockman (graduate students at Yale and Berkeley, respectively) sent meeting requests from a political organization to 191 members of Congress. Each emailed request was identical, except for the subject line—which, by random selection, identified the sender either as a donor to the member, or simply as a constituent. Senior officials, including chiefs of staff and the members themselves, were far more likely to grant a meeting to donors. In fact, landing a meeting with one of these two top-ranking figures was five times more likely when the requester was identified as a donor. Access to senior staffers overall was more than three times higher for donors than for constituents.

This may not be “corruption” in John Roberts’s imagination, but the research demonstrates a crucial point: When every other factor is the same, money alone guarantees far, far greater access to top officials. The parties, gearing up for election season, are already working this out in practice. As Politico reported yesterday, Republican officials are dreaming up new treats for donors who, newly liberated from the tyranny of overall contribution limits, are willing to give huge amounts for the party to spread around a range of candidates. “In exchange,” the story notes, “the big-money givers would get something of an ‘all access pass’ that comes with perks from the big three national committees, like face time with top officials.” Pledging not to “unilaterally disarm,” Democrats are promising to take similar steps.

To be perfectly precise, this doesn’t mean anyone is buying votes—at least not directly. For five justices, that’s just enough to maintain a straight face and insist it can’t be called corruption. But at some point, it may strain credulity to call it “democracy,” either.