Last Monday, January 11th, the U.S. Supreme Court appeared to be ruling in favor of drastically reducing the power of labor unions. In a case involving a California teachers’ union, the court may eliminate the right of public-sector unions to charge a fee to non-members. That means that all unions for government employees would operate like unions in “right-to-work” states: workers would be covered under union contracts without having to pay for the costs of bargaining them. This creates an obvious free rider program that has decimated union power in places where right-to-work is the law of the land.

Is this just one more step in the inevitable decline of the country’s organized labor movement? Are unions a relic of the past?

That’s a question Peter L. Francia and Susan Orr attempted to answer in a 2014 paper for Political Research Quarterly. Focusing specifically on Latinos, they argued that unions continue to be a force that brings people together to advocate for their own interests.

Francia and Orr noted that, despite its decline nationally, the labor movement is still strong in some places. In New York, as of 2013, almost a quarter of workers were union members, and in California more than 16 percent were. Significantly, in light of the Supreme Court case, about half of all union members in each state were government workers.

Nationally, unions are also the biggest mass-membership organizations for demographic groups traditionally underrepresented in public policy conversations—larger by far than the NAACP, La Raza, or NOW.

And union members are far more likely than non-members to engage in politics. Drawing on previous research, Francia and Orr found that participating in unions helps people gain the civic skills and knowledge they need to take part in political campaigns. That’s especially important for people with less money and free time, and who otherwise wouldn’t likely get involved.

Francia and Orr looked at just how significant unions were when it came to Latinos’ likelihood to vote. Controlling for factors including age, income, and church membership, they compared union members and their families with non-members. They found that union affiliation accounted for a 7.2 percentage point increase in the likelihood of being registered to vote and a 4.9 percentage point increase in turnout. The effect of union affiliation was significantly greater for Latinos than for the general population. This could be partly because other political groups don’t reach out to Latinos very much and because Latinos are often particularly interested in the economic issues unions focus on.

In other words, unionization could make a huge difference in Latinos’ political clout. Given that the U.S. Latino population is projected to grow by 75.5 million between 2012 and 2060, if 10 percent of that group joined a union (and if the average member had one other potential voter in their household), it would mean an additional 750,000 Latino voters. It’s possible that without the influence of organized labor, such voter turnout would be unrealizable.

Which is one reason why a Supreme Court decision that guts public-sector unions really would matter.

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