The American Civil Liberties Union is accusing the governing body of Nebraska high school sports of discrimination, claiming a referee helped deny a deaf wrestler a state championship in February.

In a letter Tuesday on behalf of Paul Ruff, a former wrestler at Gering High School, the ACLU of Nebraska said that the Nebraska School Activities Association was aware that Ruff relied on lipreading during matches, yet still assigned the only masked referee to the championship match.

“Because Paul could not heed the verbal warnings, [the referee] issued a caution point, which, combined with an earlier caution point, awarded Paul’s opponent one full point. As a result, Paul lost the match 0-1,” wrote representatives from the ACLU and the National Association of the Deaf.

According to the organizations, Ruff had never before wrestled in a match where a referee wore a mask that was not see-through. Yet, according to the letter, Bryce Abbey, the referee for the match in question, “wore such a mask…despite having knowledge that Paul is deaf and uses lipreading as the primary means of communication.”

The letter called on the NSAA to publicly acknowledge that Ruff was denied a fair shot to win the match and asked the organization to begin accommodating deaf wrestlers by making referees wear see-through masks.

In previous public comments, the head of the NSAA, Jay Bellar, defended Abbey, who he said used hand gestures during the match, and noted that Ruff gave a thumbs up, appearing to indicate that he understood the gestures. But Ruff told WOWT, a local NBC station, that the thumbs up was instead a way to ask Abbey if he was complying with Abbey’s directives.

Neither Bellar nor Abbey could be reached for comment on Wednesday.

Ruff, who has been deaf since birth, wears a cochlear implant to help hear, but he removes it for matches.

Ruff told Lincoln ABC affiliate KLKN in March that he was confused when his opponent began celebrating after being declared the winner. “I didn’t understand why because I didn’t know what was going on. I saw the point and didn’t understand why he got the point,” explained Ruff, who was a senior last year.

“I was crushed by it,” he added. “That was probably one of the worst ways possible to lose for me.”