The ministerial exception, sometimes known as the ecclesiastical exception, is a legal doctrine in the United States barring the application of anti-discrimination and other laws governing the employment relationship between a religious institution and certain key employees with ministerial roles. As the Supreme Court explained in the landmark 2012 case Hosanna-Tabor Evangelical Lutheran Church and School v. E.E.O.C., the exception is drawn from the First Amendment to the United States Constitution and serves two purposes: to safeguard the freedom of religious groups "to select their own ministers" and to prevent "government involvement in [...] ecclesiastical decisions". The first purpose is rooted in the Free Exercise Clause; the second, in the Establishment Clause.[1][2] When the ministerial exception applies, it gives religious institutions an affirmative defense against lawsuits for discrimination.[3] For example, a woman seeking to become a Catholic priest cannot sue the Catholic Church for sex discrimination over its position that women cannot be ordained as priests.[4] The Supreme Court later elaborated on when employees qualify as ministerial – and thus how broadly the exception applies – in Our Lady of Guadalupe School v. Morrissey-Berru (2020).[5]