A “declaration against penal interest” is a hearsay statement that tends to incriminate the person who made the statement.
Because people are unlikely to make statements against their interest unless those statements are true, such declarations are considered more reliable than other types of hearsay.
In Massachusetts a declaration against penal interest may be used at trial if it meets three tests:
[1] [T]he declarant’s testimony must be unavailable;
[2] the statement must so far tend to subject the declarant to criminal liability ‘that a reasonable man in his position would not have made the statement unless he believed it to be true’; and
[3] the statement, if offered to exculpate the accused, must be corroborated by circumstances clearly indicating its trustworthiness.
Commonwealth v. Dew, 443 Mass. 620, 630 (2005).
Regarding the need to corroborate declarations against penal interest, the Supreme Judicial Court has written:
Although “the judge should not be stringent” in evaluating whether a statement is adequately corroborated,…”judges are obliged to exercise a discriminating judgment” in assessing the likelihood that the declarant’s statement is true based on the circumstances of the case.
Id. at 631.