One of the most shocking political developments of last year was the speed with which Southern, Republican-controlled states embraced voter identification laws after the Supreme Court overturned section 2 of the Voting Rights Act. To critics, including myself, this was an easy call: GOP lawmakers were taking advantage of a newly permissive policy environment to suppress minority voters, and African Americans in particular.

If this sounds like an outrageous accusation, then it’s worth reading a recent paper from Keith G. Bentele and Erin E. O’Brien, which brings statistical analysis to bear on the question of voter identification laws. What they found was surprisingly straightforward: Between 2006 and 2011, if a state elected a Republican governor, increased its share of Republican legislators, or became more competitive while under a Republican, it was more likely to pass voter ID and other restrictions on the franchise. Likewise, states with “unencumbered Republican majorities” and large black populations were especially likely to pass restrictive measures. Their broad conclusion, in other words, is that these laws are the result of fierce partisan competition:

Zooming out, a straightforward picture emerges. Our analyses identify a very substantial and significant association between the racial composition of a state’s residents or active electorate and both the proposal and passage of voter restriction legislation. This association is robust across multiple modeling approaches and controlling for a wide variety of relevant factors. Further, these findings demonstrate that the emergence and passage of restrictive voter access legislation is unambiguously a highly partisan affair, influenced by the intensity of electoral competition.

Put another way, the rush for voter ID has nothing to do with fraud—which is near non-existent—and everything to do with political gain. And for Republicans who want the most bang for their voter suppression buck, African Americans are an obvious target; reduce their share of black voters in the electorate, and—in states like Florida, Ohio, and North Carolina—you cripple Democratic chances in statewide elections.

It’s not hard to see how this works. If you’re impoverished, unbanked, or otherwise outside of the mainstream economy, it’s hard to collect or purchase documents, and file for ID. Moreover, it’s simply true that, because of past discrimination and persistent racial inequality, blacks are more likely to fall into those categories. Any law that makes voting a function of resources—which is how voter identification laws work—is a law that will disproportionately harm African Americans.

If this research says anything, it’s that partisan Republicans know this, and are acting accordingly. Does this make them “racists?” I don’t know, and it doesn’t matter. What matters are outcomes, and with voter ID laws, the GOP is pursuing that one that’s unambiguously harmful to black people.