Meaning of decisory oath in English:

decisory oath

noun

Law
  • An oath given by one party in a lawsuit at the request of the other party, affirming the truth of a fact which the first party relies upon but cannot prove (and which the second party cannot disprove), and which is treated as proving the fact in question; also called decisive oath, proof by oath.

    The decisory oath was abolished in Scotland by the Requirements of Writing (Scotland) Act 1995, and had already disappeared in practice; it is occasionally still used in other Civil law jurisdictions, as in Italy.

Origin

Late 16th century.