Charles Fain Lehman of the Washington Free Beacon highlights new information that tests a common complaint about voter identification requirements.

In total, 10 states, ranging from Georgia to Wisconsin, require voters to show ID in order to vote. Seven of those states require a photo ID, and three do not. An additional 25 states “request” that voters display ID, but may still permit them to vote on a provision ballot if they cannot. The remaining states “use other methods to verify the identity of voters,” according to the National Conference of State Legislatures.

The new research, from an economics professor at the University of Bologna and another at Harvard Business School, indicates that “strict” voting laws of the type implemented in those ten states do not have a statistically significant effect on voter turnout.

To determine this, the professors took advantage of different timing of the implementation of voter ID laws in different states to construct a “difference-in-differences” analysis, looking at how voters behave in states that do and do not have strict voter ID laws, before and after those laws were implemented. They used data from the progressive data service Catalist, “a U.S. company that provides data and data-related services to progressive organizations and has a long history of collaborating with academics.”

The data from Catalist contained both demographic information—age, sex, race, and party affiliation—as well as information on whether or not a surveyed person was actually registered. This means that the paper’s authors could test whether or not voter ID not only stopped registered voters from voting, but discouraged unregistered voters from registering.

“Strict ID laws have no significant negative effect on registration or turnout, overall or for any subgroup defined by age, gender, race, or party affiliation,” the paper’s authors found.