Chris Sigler claims he was harassed by his high school principal over wearing a t-shirt in support of a gay-straight club.

Sigler, a 17-year-old senior at Sequoyah High School in Madisonville, Tennessee, has alleged that his principal shoved and verbally harassed him last week for wearing a t-shirt in support of efforts to establish a Gay-Straight Alliance (GSA) club at the school.

Sigler's homemade t-shirt read “GSA: We've Got Your Back.”

The openly straight Sigler told his family that he wanted to start the club to provide support for gay students who are at greater risk than heterosexual teens of committing suicide.

“I don't want to go to a funeral of any friend,” he told his mother, Linda Sigler.

In a letter written by the American Civil Liberties Union (ACLU) of Tennessee, the group reminded the school district that Sigler enjoys free speech and free expression rights under the First Amendment, and threatened to sue the school district.

“We demand that Monroe County Schools state in writing by Tuesday, October 11, 2011 that it will permit any Sequoyah High School student to wear clothing or accessories that peacefully express an opinion regarding the proposed Gay-Straight Alliance free from threats of discipline or physical intimidation or assault,” the ACLU wrote.

“All I want is to have a GSA at my school to help stop the bullying against gays and lesbians and their friends who support them,” Sigler said. “The shirt was a way to use my voice and show my support for the club. The way I was treated shows even more why we need a GSA here.”