A Nashville charter school issued a “Final Warning” to first-grade teacher Eric Rivera after he declined to read a language arts book featuring a same-sex married couple, according to a demand letter from First Liberty Institute.

Rivera, a Christian, requested a religious accommodation upon discovering the book in the curriculum at KIPP Nashville. According to the letter, he asked that a colleague read the book to his students while he remained in the classroom to observe, believing the arrangement would allow the lesson to proceed without violating his religious convictions.

School administrators allegedly denied the request and summoned Rivera to the principal’s office, where he was informed that adherence to the curriculum “with fidelity” was an expectation of his role. The warning letter stated that students would miss unit-aligned content due to his refusal, even though another teacher reportedly covered the material.

First Liberty’s correspondence claims the principal indicated that support for same-sex marriage was so integral to the unit that Rivera could not teach any portion of it, resulting in his removal from the first-grade classroom. The notice also warned that further disciplinary action, including termination, could follow and that the letter would be placed in his personnel file.

Cliff Martin, senior counsel at First Liberty, argued that compelling a teacher to violate his religious beliefs to maintain employment constitutes unlawful discrimination under federal civil rights law. The organization also contends the school may have failed to provide required parental notification under Tennessee law regarding certain books categorized as LGBTQ-themed.

The legal group is demanding that the warning be removed from Rivera’s record, that the school cease what it describes as religious discrimination, and that it commit to accommodating employees with faith-based objections to specific instructional materials.

The school has not publicly responded to the allegations.