Canonical impediment

In the canon law of the Catholic Church, an impediment is a legal obstacle that prevents a sacrament from being performed validly and/or licitly. The term is used most frequently in relationship to the sacraments of Marriage and Holy Orders. Some canonical impediments can be dispensed by the competent authority (usually the local ordinary but some impediments are reserved to the Apostolic See) as defined in Canon Law.

Roman Catholic sacramental theology teaches that the ministers of the sacrament of holy matrimony are the man and woman, and therefore any marriage contracted voluntarily between two baptized and unmarried adults is valid, though under ordinary circumstances the marriage must be blessed by a priest, or a deacon, to be licit. However, various provisions in current canon law lay down additional requirements for validity, in apparent contradiction of this principle.

The validity of an action is distinguished from its being licit in that the former pertains to its integrity while the latter its legality. (An analogous illustration might be that of a disbarred lawyer who wins a court case; the verdict is not overturned, but the attorney is still subject to sanctions. Similarly, a priest who has been laicized, suspended, or excommunicated is not to say Mass, but should he nonetheless do so the Mass is still considered valid.)

Impediments to marriage are classified according to many different criteria.

In regard to their effect on the sacrament, impediments are either diriment, which invalidate an attempted marriage, or prohibitive (or impedient), which make a marriage illicit but valid. "Diriment" comes from the Latin word dirimens ("separating"), that is, an impediment that means the couple cannot be joined. The 1983 Code of Canon Law does not list prohibitive impediments as such, and thus the distinction between validity and licitness is less clear than in previous formularies.

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