The U.S. Supreme Court case Board of Education of the Westside Community Schools v. Mergens (1989) revolved around a student's request to form a Christian club at her public high school, which was denied by the school on grounds that it violated the Establishment Clause of the First Amendment. The court ruled in favor of Bridget Mergens, stating that allowing students to meet for religious purposes during non-instructional time did not violate this clause and was protected under the Equal Access Act passed by Congress in 1984. This act requires federally funded secondary schools to provide equal access to extracurricular clubs regardless if they are based on religious, philosophical or political views. The ruling emphasized that as long as participation is voluntary and initiated by students without any official endorsement from school authorities, such gatherings do not infringe upon constitutional provisions separating church and state.

In the dissenting opinion for Board of Education v. Mergens, Justice Marshall, joined by Justice Brennan and Justice Blackmun, argued that allowing a student-led Bible study group to meet on school premises would violate the Establishment Clause of the First Amendment. They contended that such an allowance could be perceived as endorsement or promotion of religious activities by public schools. The dissenters also disagreed with the majority's interpretation of Equal Access Act (EAA), arguing it was not intended to apply in situations where there is potential violation of constitutional principles like separation between church and state. They believed this case presented a conflict between EAA and Constitution which should have been resolved in favor of latter.