CHARLOTTE, N.C. – A former Charlotte Catholic school teacher who claimed he was fired for being gay has filed a federal lawsuit against his former employer, saying his firing violates the Civil Rights Act.

In 2012, Lonnie Billard was named Charlotte Catholic’s Teacher of the Year. He taught English and ran the school’s theatre department before scaling back to work as a long-term substitute.

The lawsuit, filed on Billard’s behalf by the ACLU and the law firm Tin Fulton Walker & Owen claims that his firing violates Title VII of the Civil Rights Act, which prohibits employers from discriminating against employees on the basis of sex and other characteristics.

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Billard announced on his Facebook page in October of 2014 that he and his partner Rich were planning to get married in 2015. According to Billard, it wasn’t long before he was relieved of his duties.

“I got a call telling me I would not be allowed to teach anymore,” Billard told WCNC. “As it was explained to me that because I had posted on Facebook to my friends that my longtime partner Rich — Rich and I were going to get married this spring. Apparently there were a couple of teachers that were unhappy with that.”

David Hains, spokesperson for The Charlotte Roman Catholic Church Diocese, the organization that oversees Charlotte Catholic, says Billard was fired because he went against teachings of the Catholic Church.

“Well, the Catholic Church opposes same-sex unions,” Hains said in a statement. “Marriage can only be between one man and one woman. He’s not being picked on because he’s gay. He lost his job as a substitute teacher because he broke a promise because he chose to oppose church teaching, something he promised he would not do.”

Billard said at the time of his employment, most people at the school knew he and Rich were a gay couple, with Rich often coming to school events.

“I loved being part of the Charlotte Catholic school community, and the classroom has always felt like home to me,” Billard said. “I know that the Catholic Church opposes same-sex marriage, but I don’t think my commitment to my husband has any bearing on my work in the classroom. I have never hidden the fact that I’m gay and my relationship with my partner was no secret at school. But whether or not the school previously knew that I am gay is not the point. People should be able to fall in love and get married without risking their jobs.”