The Books Save Lives Act requires public schools and public libraries that receive federal funding to maintain diverse book collections including works written by or about members of underrepresented communities, such as racial and ethnic minorities, LGBTQ individuals, religious minorities, and people with disabilities. The bill also mandates that all covered schools employ a trained librarian to staff their library. Additionally, the legislation treats the exclusion of books about underrepresented communities as potential evidence of civil rights discrimination, allowing it to be challenged under existing federal civil rights laws. Within 180 days of the law's enactment, the Comptroller General must prepare a report examining how recent book banning campaigns in public libraries and schools have affected underrepresented communities. The bill affects elementary and secondary schools, as well as public libraries that receive any federal financial assistance.