Clandestinity is a diriment impediment in the canon law of the Roman Catholic Church. It requires the presence of witnesses to the marriage vows, one of which must be a priest, in order for the marriage to be valid.
It was promulgated in the 16th century by the Council of Trent in the decree called Tametsi. Prior that time, an unwitnessed exchange of marriage vows was deplored but valid, and the decree was enforced only in those regions where it could be proclaimed in the vernacular
The witnesses must be the parish priest, or another priest with permission either from the parish priest or the local ordinary, and the other two witnesses must be capable of giving witness to the marriage vows.
It was later modified, by the decree Ne Temere, to require specific priests, such as the local pastor of the couple's residence.
Further modifications provided that the priest was not necessary if one of the marrying parties was in danger of death, or the vows could not be exchanged before a priest in a reasonable amount of time.
- Catholic Encyclopedia "Clandestinity (in Canon Law)"
- "marriage without a priest" from New Catholic Dictionary