A declaration against interest is an exception to the hearsay rule, which prohibits introduction of out-of-court staments of unavailable witnesses. It is a statement that is against the maker's financial interests or risk of legal liability to such an extent that no reasonable person would make such a statement unless he/she believed it was true. For this reason, courts allow it in evidence as an exception to the hearsay rule because of the special trustworthiness of the truthfulness of such statements. It is distinguished from an admission because, unlike a declaration against interest, an admission need not be against the declarant’s interest at the time it is made; thus even a statement that seems neutral or self-serving at the time it is made may be introduced against the party who made it.
At common law, there are three main requirements for the exception:
- The declaration must have been against the declarant’s pecuniary or proprietary interest (not his penal interest) when made;
- The declarant must now be unavailable; and
- The declarant must have had first-hand knowledge of the facts asserted in the declaration.
Federal Rule of Evidence (b)(3) follows this approach, except that declarations against penal interest are also admissible (except uncorroborated statements exculpating the accused).