MISSOURI (AP) — A school district in southwestern Missouri decided to bring back spanking as a form of discipline for students — if their parents agree — despite warnings from many public health experts that the practice is detrimental to students.

Classes resumed Tuesday in the Cassville School District for the first time since the school board in June approved bringing corporal punishment back to the 1,900-student district about 60 miles (100 kilometers) southwest of Springfield. The district had dropped the practice in 2001.

The policy states that corporal punishment will be used only when other forms of discipline, such as suspensions, have failed and then only with the superintendent’s permission.

Superintendent Merlyn Johnson told The Springfield News-Leader the decision came after an anonymous survey found that parents, students and school employees were concerned about student behaviour and discipline.

“We’ve had people actually thank us for it,” he said. “Surprisingly, those on social media would probably be appalled to hear us say these things, but the majority of people that I’ve run into have been supportive.”

Parent Khristina Harkey told The Associated Press on Friday that she is on the fence about Cassville’s policy. She and her husband did not opt-in because her six-year-old son, Anakin Modine, is autistic and would hit back if he were spanked. But she said corporal punishment worked for her when she was a “troublemaker” during her school years in California.

“There are all different types of kids,” Harkey said. “Some people need a good butt-whipping. I was one of them.”

Morgan Craven, national director of policy, advocacy and community engagement with the Intercultural Development Research Association, a national educational equity nonprofit, called corporal punishment a “wildly inappropriate, ineffective practice.”

The US Supreme Court ruled in 1977 that corporal punishment is constitutional and left it up to states to set their own policies. Craven said 19 states, many in the South, have laws allowing it in schools. The most current data from 2017-18 shows about 70,000 children in the US were hit at least once in their schools.

Students who are hit at school do not fare as well academically as their peers and suffer physical and psychological trauma, Craven said. In some cases, children are hurt so badly that they need medical attention.

“If you have a situation where a kid goes to school and they could be slapped for, you know, some minor offense, it certainly creates a really hostile, unpredictable and violent environment,” Craven said. “And that’s not what we want for kids in schools.”

But Tess Walters, 54, the guardian of her eight-year-old granddaughter, had no qualms about signing the corporal punishment opt-in papers. She said the possibility of being spanked is a deterrent for her granddaughter, who has attention-deficit/hyperactivity disorder.

“I’ve read some people’s responses on Facebook recently, and they’re just going over the top like, ‘Oh, this is abuse, and, oh, you’re just going to threaten them with, you know, violence.’ And I’m like, ‘What? The child is getting spanked once; it’s not beatings.’ People are just going crazy. They’re just being ridiculous,” Walters said.

Disabled students also are more likely to be subjected to corporal punishment, said Elizabeth Gershoff, a professor of human development and family sciences at the University of Texas at Austin. She said that led four states — Tennessee, Oklahoma, Mississippi and Louisiana — to ban using it for those students.

She noted that overall, corporal punishment is on the decline, with the numbers dropping steadily since the federal government started tracking it in the late 1970s.

“Most schools are realising, ‘You know what, we can discipline children, we can guide their behaviour without hitting them,'” said Gershoff, who authored the 2016 study with Font.

In Missouri, periodic efforts to ban corporal punishment in schools have failed to gain traction in the Legislature. The state does not track which districts allow spanking because those decisions are made at the local level, a spokeswoman for Missouri’s K-12 education department said.

US senator Christopher Murphy, a Connecticut Democrat, is pushing for a ban on the use of corporal punishment in schools that receive federal funding. He has called it a “barbaric practice” that allows teachers and administrators to physically abuse students.