Formal act of defection from the Catholic Church

A formal act of defection from the Catholic Church (Latin actus formalis defectionis ab Ecclesia catholica) was an externally provable juridic act of departure from the Catholic Church, which was recognized from 1983 to 2010 in the Code of Canon Law as having certain juridical effects enumerated in canons 1086, 1117 and 1124. The concept of "formal" act of defection was narrower than that of "notorious" (publicly known) defection recognized in the 1917 Code of Canon Law and still narrower than the concept of "de facto" defection. In 2006, the Pontifical Council for Legislative Texts specified in what a formal act of defection from the Catholic Church consisted. In 2009, all mention of a formal act of defection from the Catholic Church and of any juridical effects deriving from it was removed from the Code.

Between 1983 and 2006, the Catholic Church in Germany and some other countries treated as a formal act of defection from the Catholic Church the declaration that some made to the civil authorities for the purpose of avoiding the extra tax traditionally collected by the state for the benefit of whatever Church the tax-payer was a member of. The Church in those countries considered people who made this declaration as no longer entitled to the privileges of membership of the Church, such as having a wedding in church.

The 2006 notification ruled that such declarations did not necessarily indicate a decision to abandon the Church in reality. It laid down that only the competent bishop or parish priest was to judge whether the person genuinely intended to leave the Church through an act of apostasy, heresy, or schism. It also pointed out that single acts of apostasy, heresy or schism (which can be repented) do not necessarily involve also a decision to leave the Church, and so "do not in themselves constitute a formal act of defection if they are not externally concretized and manifested to the ecclesiastical authority in the required manner."

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