The achievement gap between black students and their peers is well documented, but conclusive explanations of the reasons for the gap are harder to come by.
Now a study of more than 15,000 students in Kentucky says that as much as 20 percent of the difference may be due to a single cause: getting suspended from school.
“This analysis — the first of its kind — reveals that school suspensions account for approximately one-fifth of black-white differences in school performance,” write sociology professors Edward W. Morris and Brea L. Perry in the study, published in the journal Social Problems last month.
Morris and Perry analyzed the test scores and discipline records of 16,248 students in grades 6 through 10, using data collected by the Kentucky School Discipline Study from 2008 to 2011.
Even after controlling for other factors, such as socioeconomic status and disabilities, they found a strong correlation between suspension and lower scores on end-of-year tests.
The study notes that black students are more likely to be suspended than their white and Asian classmates. Black students are more likely than whites to attend schools that use more “exclusionary discipline,” such as suspension and expulsion, the study says. Even within the same school, they are also more likely to be suspended.
And students who are suspended do worse on end-of-year tests — worse than their classmates, but also worse than they do themselves in years when they’re not suspended, the study found.
The authors arrived at the 20 percent figure through a statistical model known as mediation. First, they determined the effect of race and ethnicity on achievement. Next, they added the students’ history of suspension as another variable in the model. By seeing how much the effect of race or ethnicity went down with that added variable, they were able to conclude that racial or ethnic differences in suspension account for 20 percent of racial differences in achievement.
The bottom line? It’s pretty significant.
“It’s a lot, yeah,” Perry said. “But you have to understand that the racial disparities in discipline are huge — bigger than the racial disparities in achievement.”
Morris and Perry caution that the link between suspension and lower performance doesn’t mean one causes the other. They say more research would clarify whether it’s the missed instructional time or the punitive nature of suspension, or both, that hurts performance.
It’s also possible, they say, that black students are suspended more often because they misbehave more often — but “we can draw from previous studies,” they add, “which have noted that minority students are disciplined more harshly than white students for similar misbehavior.”
The authors conclude that suspension, in general, lowers school performance and contributes to large racial gaps in achievement.
“Particularly for African American students in our data,” Morris and Perry write, “the unequal suspension rate is one of the most important factors hindering academic progress and maintaining the racial gap in achievement.”