A Black Pennsylvania high school student was told to remove his “Black Lives Matter” mask during his graduation ceremony.

Dean Holmes says that he was allowed to continue through with his graduation from York Catholic High School after he complied with their demands to remove the mask. His father, however, took to Facebook to call out the school for putting his son at risk to contract COVID-19 and says the school discriminated against his son because of his race and his prior involvement in civil rights activism at the school.

“As a parent, I will not stand for my son being humiliated publicly, having his basic human dignity crushed on what should have been one of the happiest days of his young life,” John Holmes wrote in the lengthy post.

“My son literally was discriminated against in plain sight based on his race and his prior civil rights activism, and this latest action is part of a pattern and practice of discrimination at York Catholic and it cannot stand unchallenged,” he continued. “One can only graduate from high school one time and for him to have to suffer this injustice is reprehensible. The dissatisfaction that he felt by being pulled out of line and forced to remove his mask was both incalculable and traumatic and will follow him the rest of his life.”

The school has since released a statement saying that they do not allow messages of any kind on the students’ caps or gowns and were following the same protocol for the masks.

“Each graduate was given a face shield to be worn in lieu of a face mask,” Arthur Full, Chairman of York Catholic School Board, wrote in a statement. “Graduates gathered outside the church prior to processing inside. They were checked in, asked several questions regarding exposure to COVID-19 and temperature checked. Two other graduates chose to wear a solid face mask with no writing in addition to the actual shield and sought permission in advance to do so.”

Full continued, “It was not until the last minute, right before entering the church, that the face mask with writing was put on. York Catholic administration directed the face mask to be removed privately, away from the other graduates and guests.”