The U.S. Supreme Court case Board of Education of Central School District No. 1 v. Allen, Commissioner of Education of New York, et al., dealt with the issue of whether a state could provide textbooks to students attending religious schools without violating the Establishment Clause in the First Amendment which prohibits government from making any law "respecting an establishment of religion". The court ruled in favor of Allen by a vote count 6-3, stating that providing textbooks to all students regardless if they attend public or private school does not constitute as promoting one religion over another and therefore is not unconstitutional under the Establishment Clause. This decision was based on the principle that such aid did not advance or inhibit any particular religious practice but rather served secular educational purposes.

In the dissenting opinion for Board of Education of Central School District No. 1 v. Allen, Justice William O. Douglas argued that providing textbooks to students attending religious schools was a violation of the Establishment Clause in the First Amendment, which prohibits government endorsement or support of religion. He contended that such provision constituted financial aid to religious institutions and could potentially lead to governmental control over these institutions, thereby threatening their independence and autonomy. Furthermore, he expressed concern about potential conflicts arising from determining what constitutes a "secular" textbook versus a "religious" one - an issue he believed should not be within the purview of government officials or courts due to its inherently subjective nature.