Education Secretary John King speaks during the daily briefing at the White House in Washington, Thursday, Sept. 29, 2016. CREDIT: AP/Susan Walsh

More than one third of students who experienced corporal punishment were black.

Corporal punishment, such as paddling and hitting students, may seem like a thing of the past, but many schools still continue the practice. U.S. Secretary of Education John King released a letter to schools on Tuesday, asking educators to end this form of punishment.

“Our schools are bound by a sacred trust to safeguard the well-being, safety, and extraordinary potential of the children and youth within the communities they serve,” King said in a press call on the issue. “No school can be considered safe or supportive if its students are fearful of being physically punished.”

He added that the practice disproportionately affects students of color and students with disabilities. More than one-third of students who experienced this form of punishment in the 2013–2014 school year were black. Boys made up 80 percent of students who were corporally punished. There did not appear to be any significant disparity in punishment by gender when it to black students, however.

“No school can be considered safe or supportive if its students are fearful of being physically punished.”

In total, 110,000 students across the country were subjected to corporal punishment over the 2013–2014 school year.

The Department of Education released a map showing which parts of the country had the highest percentage of students who received corporal punishment that year. High use of corporal punishment was concentrated in the Southern U.S. It has been banned in 28 states and the District of Columbia.

CREDIT: U.S. Department of Education

Research released in October by the Society for Research in Child Development found that more than 160,000 students in 19 states experience corporal punishment in school each year. Mississippi and Alabama were particular outliers when it came to corporally punishing more black children than white children. One-fifth of the districts in both of the states were five times more likely to spank or paddle black children than white children.

King’s appeal to school districts to stop paddling students went beyond a moral plea, however. He also called the practice ineffective. King pointed to research showing that corporal punishment hurts brain development and is associated with poorer academic outcomes. Research shows that, in the short term, students who are punished in this manner simply become more aggressive and defiant; in the long term, they may experience struggle with substance abuse and mental health issues.