HOOVER, Alabama -- The Southern Poverty Law Center sent a letter to Hoover High School officials today asking they stop censoring students or face a federal lawsuit.

The warning comes after a 15-year-old student, Sara Couvillon, was told this month she couldn't wear a T-shirt that read, "Gay? fine by me."

According to the SPLC, school officials told Sara they were concerned for her safety, but Sara said she did not experience threats of violence, nor did school officials confirm there had been threats. The teen had routinely worn the T-shirt during the last school year without incident.

SPLC lawyers say students shouldn't be prevented from expressing acceptance of lesbian, gay, bisexual or transgender people. The letter warns school officials to rescind their practice of unlawfully censoring students by Sept. 12, or the SPLC will file suit.

"There are kids at my school who really want to be themselves, but they don't have the strength they need," Sara said in a news release issued today by the SPLC. "It isn't easy being singled out, but if I can give someone else the courage to be who they are then it's worth it to me."

Efforts to reach Hoover school officials for comment weren't immediately successful.