The superintendent of a Texas public school district is drawing harsh criticism after issuing a written threat Tuesday to suspend any students who take part in demonstrations about gun violence after the school shooting in Florida last week.

Curtis Rhodes, the superintendent of the school district in Needville, a small town southwest of Houston, wrote a letter to students and parents that was distributed Tuesday on the social media page for the town’s high school. It began with a reference to the protests around the country after a shooting in Parkland, Fla., left 17 people dead.

“Please be advised that the Needville ISD will not allow a student demonstration during school hours for any type of protest or awareness!!” Rhodes wrote. “Should students choose to do so, they will be suspended from school for 3 days and face all the consequences that come along with an out of school suspension. Life is all about choices and every choice has a consequence whether it be positive or negative. We will discipline no matter if it is one, fifty, or five hundred students involved.”

Rhodes — a registered Republican, according to public records — said parental notes would make no difference.

“Respect yourself,” Rhodes wrote, “and please understand that we are here for an education and not a political protest.”

The move touched off an outcry after students from Marjory Stoneman Douglas High School called on elected officials to curb gun violence. And it comes as schools around the country are having difficult conversations about campus security amid the regular occurrence of school shootings.

Constitutional scholars described Rhodes’s threats as a blatant violation of free-speech rights.

“It’s a quintessential First Amendment violation, and most Americans have an instinct about that,” Heidi Li Feldman, a professor at Georgetown Law, said in an interview. “What’s really weird about this is that they announced they will suspend people over the content of their off-campus protest. Content-based restrictions on speech are anathema to the First Amendment. So this looks like a total problem.”

Rhodes did not respond to an emailed request for comment. His voice-mail box at the school was full.

The high school’s Facebook page was no longer available on Tuesday night.

Other schools have sought to curtail student protests as well, though in less blunt terms.

Steven Walts, the superintendent of schools in Virginia’s Prince William County, also threatened students with disciplinary measures for missing school for protests over gun control.

“PWCS recognizes your right to free speech and to protest, but these rights do not extend to disrupting classes or to leaving school,” he wrote in a letter to parents Wednesday. “Students who cause disruptions or leave school without authorization will face disciplinary consequences, in keeping with the PWCS Code of Behavior.”

Feldman said that disciplinary measures for missing school and other policy violations must be handed out uniformly — and not just for those who are protesting — to be legally sound.

Feldman said that Rhodes’s move was reminiscent of an Iowa school district’s attempt to prevent students from wearing black armbands in protest of the Vietnam War in the 1960s, which prompted a challenge that resulted in a landmark Supreme Court ruling, Tinker v. Des Moines.

Officials from the city’s school district had sent 13-year-old Mary Beth Tinker home from school for wearing the armband and later suspended four other students at the school. The Supreme Court sided overwhelmingly with the students, ruling that students — and teachers, for that matter — do not “shed their constitutional rights to freedom of speech or expression at the schoolhouse gate.”

Rhodes has been at the center of legal disputes before.

In 2008, a decision he made to forbid a Native American kindergarten student from wearing long hair was ruled to be a violation of the child’s right to religious freedom twice, by federal district and appeals courts.

“We’re not going to succumb to everything and just wash away our policies and procedures,” he told the Houston Press about his stance in the case, describing Needville as a place of tradition.

“A school district is a reflection of the community,” he said. “We’ve consistently been very conservatively dressed, very conservatively disciplined. It’s no secret what our policy is: You’ll cut your hair to the right point. You’ll tuck in your shirt. You’ll have a belt.”

High students chant calls for action as they march to the federal courthouse building Wednesday in Tucson. Students at dozens of U.S. high schools walked out of class Wednesday to protest gun violence and honor the victims of last week’s deadly shooting at a school in Florida. (Mike Christy/Arizona Daily Star/AP)

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