Declaration against interest is a statement made by a declarant who is unavailable that is against the declarant’s pecuniary, proprietary, or penal interest when it was made. A statement against interest is admissible as an exception to the hearsay rule according to the Federal Rules of Evidence 804(b)(3) and similar state laws. The general rule against hearsay prevents out of court statements being used in court because these statements may be untrustworthy. Evidentiary rules allow an exception for a declaration against interest under the reasoning that a person would rarely say something that would be against their interests unless it were true. Policymakers allow this exception because they find the greater trustworthiness of these statements justify their use because they often can be key to cases where a witness is unavailable.
In order for a statement to meet this exception, it must meet a few requirements under the Federal Rules of Evidence. First, the declarant must be unavailable as a witness. Second, the party offering the statements must prove that the statements would harm the declarant’s legal claims against someone or aid in legal claims against themselves. For example, if a declarant said they had multiple drinks before crashing into another vehicle, that statement would be against the interests of the declarant in a driving under the influence case. Lastly, in a criminal case, there must be other circumstantial evidence that makes the statements more trustworthy. These requirements vary between states and the federal rules of evidence, but they generally all have similar requirements to the Federal Rules. Also, a declaration against interest potentially will not be admissible if circumstances call into question the trustworthiness of the statement. For example, a declaration against interest may be inadmissible if the declarant was being forced into making the statement.
[Last updated in October of 2022 by the Wex Definitions Team]