Civil rights groups filed a lawsuit Thursday on behalf of a transgender boy prevented by Tennessee law from joining the boys’ golf team at his high school.

The suit challenges S.B. 228, which requires that a middle or high school student’s gender, for purposes of interscholastic athletics, be determined by the student’s assigned sex at birth as indicated on the birth certificate. The bill passed in the legislature in March and was signed into law by Governor Bill Lee. S.B. 228 is one of a number of bills in Tennessee that limits transgender rights.

The suit, filed by Lambda Legal and the ACLU, alleges that S.B. 228 was not enacted for the ostensible purpose of protecting girls in sports but was “part of a wave of legislation in Tennessee and across the country targeting transgender people for disapproval and exclusion from full participation in society.” The suit claims that the law discriminates on the basis of sex and gender status in violation of Title IX and the equal protection clause under the Fourteenth Amendment. The boy, Luc Esquivel, and his parents are seeking to permanently enjoin enforcement of the law.

Luc said in a statement, “I can’t control the law that was passed, but just because it was passed, it doesn’t mean it was right.” He urged other trans youth “to fight for what you believe is right and to stand up for yourself. Nothing gets done if you don’t do anything about it.”