We’ve just seen the first two contests of the 2016 elections, and just in time, there’s a new paper from the University of California, San Diego, that shows what we already suspected. That is, voter ID laws dampen turnout for minorities.

Voter ID laws adversely affected the turnout of minorities, and particularly that of Latinos, the paper found. The study also revealed that turnout among Democrats was disproportionately affected, backing up claims of a political motivation behind the laws, which have been overwhelmingly championed by GOP legislators.

It is the first comprehensive study that’s been done over many election cycles that very clearly shows how minority voters are affected, and how they’re adversely and disproportionately affected compared to their white counterparts, the authors say.

Lajevardi, a Ph.D. candidate in UC-San Diego’s department of political science, is joined on the study by lead author Zoltan L. Hajnal , a political science professor there and with Lindsay Nielson, a post-Doctoral fellow. They examined not just the turnout, but the gap among racial groups compared with white voters. Looking at states with strict photo ID laws in elections from 2006 through 2012, they found, where they are enacted, racial, and ethnic minorities are less apt to vote.

Not only have the numbers of states passing voter ID laws grown considerably since the Supreme Court approved of Indiana’s photo ID law in 2008, the requirements in the laws have also gotten stricter. The paper’s authors thus focused attention on “strict” photo ID laws, meaning those “that prevent the voter from casting a regular ballot if they cannot present appropriate identification.” Seven states have strict photo ID laws in place, by the study’s count.

In general elections, states with strict photo ID laws show a Latino turnout 10.3 points lower than in states without them, the study showed. The law also affected turnout in primary elections, where Latino turnout decreased by 6.3 points and Black turnout by 1.6 points.