EDMOND, Okla. – The American Civil Liberties Union is threatening an Oklahoma high school where administrators forced a student to remove a Black Lives Matter shirt and warned about possible disciplinary action for students who planned to protest the incident.

Deer Creek High School junior Dacoven Roberson told KFOR he received a dress code violation for wearing a Black Lives Matter hoodie to school on Wednesday, and posted about it on Snapchat.

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“And they say they’re not racist lol okay!” Roberson wrote in the post. “Soo who tryna protest? … I just got sent to the office for wearing my Black Lives Matter hoodie in a predominantly white school.”

“I was hurt, so I posted something to my story,” he said. “Which they screenshotted and posted on their story, and so on.”

The viral post quickly prompted some students to plan a protest by wearing white or black to school, while others discussed an opposition protest, he said.

“Some other kids took that to wow, they’re doing black, we’ll do white. Or they’re wearing Trump, which, like, really didn’t have anything to do with it,” Roberson said.

That’s when Deer Creek High School Principal Melissa Jordan intervened with an email to parents.

“It has been brought to our attention through student social media postings that some students may be planning to wear white or black shirts tomorrow in an effort to create division,” she wrote. “Any behavior or action that has the potential to disrupt may result in disciplinary action.”

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Roberson said he really likes his Black Lives Matter hoodie and thinks being forced to remove it, as well as the principal’s message, violates students’ free speech rights.

“The shirt kind of means a lot to me and she told me to take it off,” he groaned. “And I told her it had nothing to do with race or anything like that. It’s just saying equality.”

ACLU-Oklahoma Legal Director Brady Henderson is now threatening Deer Creek administrators with legal action if they don’t take several specific steps to repent for their alleged transgressions.

“While we have yet to verify directly these reports, it should be noted that if they are accurate, such an action by the school would be a clear and obvious violation of the First Amendment in and of itself,” Henderson wrote in a letter to school officials about Roberson’s allegations, according to KOKH.

The ACLU demands that Deer Creek officials immediately retract the principal’s letter and issue and apology to the school community, reverse and expunge any discipline issued to students, investigate Roberson’s allegations about being forced to remove his BLM sweatshirt and “impose appropriate discipline on whatever staff or faculty members were responsible, including, if warranted, suspension or termination of employment.”

Lastly, to investigate other claims from non-white students about being harassed by white racist students and to “create and effect a plan of action for authentic training, dialogue, and accountability for faulty and administrators concerning their duty to provide an education environment open and welcoming to all Deer Creek students, not just the white ones,” Henderson wrote.

“Should the initial steps to mitigate the constitutional violations discussed above not be taken by Friday, May 5, we will presume that the District intends to defend its conduct in court rather than work to correct it voluntarily,” the letter read.

Deer Creek Superintendent Ranet Tippens told KOKH “Deer Creek Schools is reviewing the allegations and we will take this matter very seriously.”