When Republicans won control of the Wake County, North Carolina school board in 2009, they promised to eliminate the district’s racial integration program in favor of “community schools” closer to students’ homes — and they did. By 2012, Democrats had retaken control and were trying to change course.

The shifts caught the attention of Duke professor Hugh Macartney, who wondered whether party labels predict how school boards will address — or fail to address — school segregation.

Now, a new study released by Macartney and John Singleton of the University of Rochester suggests that Wake County was not unique. Electing Democratic school board members, they found, leads to less-segregated schools.

The results are substantial: Electing at least one Democrat leads to students being “reassigned in such a way that the school board is now 18 percent closer to achieving the district [average racial breakdown] for each school,” said Macartney.

The first-of-its-kind paper, which is set to be released through the National Bureau of Economic Research, examines hundreds of school board elections in North Carolina between 2008 and 2012. The researchers compared districts that narrowly elected Democrats to those that narrowly elected non-Democrats — largely Republicans, but including independents. (Like most school board races, the North Carolina elections were technically nonpartisan; the researchers later matched school board candidates to the party they were registered with.)

Racial segregation was likely reduced, Macartney and Singleton show, by changes to school attendance zones. Non-Democrats made fewer changes, “potentially allowing residential sorting to increase segregation without substantial intervention,” the paper says.  

“The reductions in segregation with the change of the school board are really interesting and line up with, anecdotally, what we’ve seen in some school districts that have made strong moves on this front,” said Halley Potter a senior fellow at the Century Foundation, a progressive think that that backs school integration.

Democratic efforts to reduce segregation may have caused one unintended — albeit unsurprising — consequence: “white flight,” the migration of white families out of a district in order to avoid integration efforts.

The study shows that electing a Democrat leads to a reduction in the share of white students attending the public school district, though the research can’t definitely identify the cause. This effect does not wipe out the integration gains, though.

Potter notes that some of the departing families may have left heavily white districts, which would not hamper integration efforts. She also points out that the effect may have been caused by families of color entering the district as opposed to white families leaving.

The paper has not been formally peer-reviewed. But David Deming, a Harvard economist who has examined segregation in North Carolina and briefly reviewed the study, said the authors used a well-established research approach.

The study highlights the importance of school board elections, given the ability of one policymaker to ameliorate segregation — as well as the diverging education agendas of different parties.

“Policymaking is all about trade-offs, and we should expect Republicans to prioritize different things than Democrats do. Like achievement and choice, for example,” said Mike Petrilli of the Fordham Institute, a conservative education think tank.

But a number of studies have shown that more integrated schools improve the achievement of low-income and black students. Deming’s research found that the end of busing-based integration efforts in Charlotte led to higher crime rates and lower achievement among students of color.

Macartney’s study doesn’t look at the effect of a board’s partisan makeup on student outcomes. He also found no link between changes in economic — as opposed to racial — segregation in schools and a board’s political leanings.

In addition to the changes in enrollment zones, one possible explanation for the results is Republican support for school choice policies. Other research has found that North Carolina’s charter schools have increased segregation.

However, Potter says one way to make integration more politically tenable is to include some parent choice in assignment systems designed to prioritize diversity.

Wake County, she said, is one example of the power of school board elections to derail such integration plans. The study, Potter said, “reveals some precariousness that we want to think about — how to set up enrollment plans and priorities that can’t be unwound with one election.”