In a new national analysis, researchers find charter schools slightly contribute to school segregation. 

Conducted by researchers at the Urban Institute, the paper includes an analysis of more than 4,500 K-12 public schools from 1998 to 2015, finding that while the segregation of black and Hispanic students has remained relatively stable in the past 15 years, and has even declined in some metropolitan areas, charter schools increase segregation within districts. 

If the average district had no charter schools, researchers wrote, the segregation of black and Hispanic students would decrease by 5%.

However, the same study found that in bigger metropolitan areas, charter schools decrease segregation between districts. So while charter schools deepen the racial divide among schools, they increase diversity across districts in the same metropolitan area. 

Part of this might be explained by the inherent function of charter schools, which resembles the purpose of magnet schools in the desegregation era. Magnet schools were established to counteract white flight to suburban areas by offering custom curricula and programs in urban schools that would attract white families. 

Now, charter schools are often established to serve the specific needs of communities and, as a result, cater to populations across district lines that could benefit from the programs the schools offer. In the process, the research suggests, charters attract the communities which they are founded to serve and can lead to racial isolation. 

The authors point out that the study could not determine whether the segregation was born from excluding or specifically serving minority communities. However, researcher and author of the analysis Tomas Monarrez does point out that, historically, racial isolation has had a detrimental effect on students. 

Analysis of desegregation plans following the U.S. Supreme Court's 1954 ruling in Brown v. Board of Education found black students were less likely to drop out of high school or be incarcerated and were more likely to be healthy, employed and earn better wages, the researchers write. Termination of desegregation orders led to an increase in dropout and incarceration rates of students of color.

Still, charter schools' share of total student enrollment nationally has increased from less than 1% to 7% in less than two decades. 

While the current segregative effect of charter schools within districts varies by state, numbers in the study show segregation notably increased with the introduction of charter schools in Louisiana, New Mexico, North Carolina, Oklahoma and Rhode Island. States where charters seem to have little or no effect on segregation include Arizona, Florida, New Jersey and Oregon. 

“As districts consider expanding school choice, school boards of the communities should take into consideration this evidence to put things in perspective,” Monarrez said. He noted that the findings offer objective evidence for districts debating whether to expand charter schools. 

The study, however, does little to settle the national debate between charter school advocates, who say charter schools encourage racial integration, and critics, who say charters are prompting resegregation in America. Findings show that while charter schools’ impact on segregation is small, they do lead to slightly higher levels of racial and ethnic segregation overall — while, in some cases, decreasing segregation in large metropolitan areas. 

Proponents like the National Alliance for Public Charter Schools (NAPCS) emphasize that segregation under a school choice environment is “fundamentally different” from de jure segregation prior to Brown, and point out that charter schools do, in some ways, reduce segregation.

“Any efforts aimed at integrating schools should not come at the cost of students having access to high-quality schools,” said Nathan Barrett, senior director of research and evaluation at NAPCS.

Charter schools designed to increase integration, or "diverse-by-design” charters, combined with strategies to increase diversity — such as weighted admission lotteries and recruitment efforts targeted at minority communities — could serve to mitigate the segregative effects noted in the study, the authors write.

Centralizing school-choice options into the common enrollment systems has also been found to increase the proportion of disadvantaged students entering charter schools. And strategically locating charters to increase diversity or funding better transportation systems for students could also go a long way to ensure charter schools are serving diverse populations. 

“With the right design features, the promise of school choice as an agent of integration may yet be realized,” the authors write.