The viral video of a Richland County, South Carolina, sheriff’s deputy tackling a student at Spring Valley High School in Columbia has understandably outraged many people.

Whatever new information emerges about what precipitated Deputy Ben Fields’s decision to drag the student out of her desk and handcuff her, the case is unusual. Fields has been placed on leave, and the Department of Justice is investigating the incident.

But however extreme the Columbia case may be, it is not unusual for school discipline to fall heavily on black students, either in South Carolina or nationwide. Across the U.S., African Americans are more likely to be disciplined and to face harsher sanctions. One reason may be the increasing presence of police in schools. The video “shows the dangers of increased police presence in schools ... we are seeing this conflation between safety and discipline,” Janel George of the NAACP Legal Defense Fund told The Guardian.  

At the same time, however, school discipline is its own universe, but one that reflects the way the criminal-justice system handles adults. In both systems, African Americans, and African American men in particular, tend to be penalized at higher rates and more harshly.

South Carolina is one of the 19 states that still allows corporal punishment in schools.

According to Palmetto State law, “The governing body of each school district may provide corporal punishment for any pupil that it deems just and proper.” Unlike in some states, there’s no need to get parental permission first. (Corporal punishment delivered in loco parentis is also exempt from state law governing child abuse.)

Nationwide, corporal punishment is doled out far more to black children than white ones or Hispanic ones. “Black children were nearly two-and-a-half times more likely to be corporally punished than White children, and nearly eight times more likely to be corporally punished than Hispanic children,” the Children’s Defense Fund calculated in 2014. CDF found that 838 students are hit a day in U.S. public schools.

South Carolina isn’t one of the biggest states for corporal punishment, with about 150 cases in 2011-2012, according to Department of Education figures. But those students who are punished are highly likely to be African American. Black students make up 36 percent of South Carolina schools, but they account for 58 percent of corporal punishment cases.

Expand out to discipline overall and the disparities get starker. A University of Pennsylvania study found that 60 percent of suspended students in the South Carolina are black. (The analysis found large disparities across the South, as compared to the national average.) A 2013 report by the South Carolina Advisory Commission to the U.S. Commission on Civil Rights found something similar by studying three specific districts.

“In all three school examined districts, African Americans were significantly more likely to be suspended and placed into alternative education programs than white students,” the committee found. “In addition, in two of the three districts African American students were also much more likely than white students to be expelled.”

These problems tend to snowball: Children are suspended and fall behind on school work; once behind, they misbehave more and are disciplined further, creating a vicious cycle.

The USCCR report continued:

As the public education system appears to work effectively for many white children, regardless of household income status, the noted racial disparities in school discipline prompt the South Carolina Committee to wonder why public education does not seem to work so well for children of color in this country. If there is no racial bias in the administration of discipline, as school officials insist, why do children of color “act out” more in school than white children?

While South Carolina offers a strong case study in these problems, it’s not unusual. The “discipline gap” is a subject of concern among educators and researchers nationwide. In January 2014, the Departments of Education and Justice issued guidance to districts on how to try to close the gap.

What explains the gap? Perhaps in some cases it is outright racism. But more often, it is likely muddier. Take implicit bias, for example. Just as studies have found that blacks are prosecuted for marijuana at higher rates than whites—even though whites are actually more likely to use it—black students in one North Carolina analysis were found to be suspended more frequently for the same offenses than white ones. Socioeconomic factors likely play a role, though many of those are attributable in part or full to structural racism. Other speculation points to cultural differences.

One of the more striking things about the videos from South Carolina is the impassivity of the other students in the classroom. Other than the student filming, the others look on, somewhat frozen. Perhaps that’s because seeing a black student harshly dealt with simply didn’t register as unusual for them.