Hearsay is a statement that (1) the person making it (the declarant) does not make while testifying at the current trial or hearing (in other words, the statement is made out of court); and (2) a party offers as evidence to prove the truth of the matter asserted in the statement.

Hearsay is generally not admissible as evidence—but there are many exceptions to hearsay, and statements that are non-hearsay. The law governing hearsay is usually located in the applicable state or federal rules of evidence, which are interpreted and applied by courts in court opinions or cases.

In Illinois, hearsay is defined similarly to the federal standard, as an out-of-court statement offered in court to prove the truth of the matter asserted. Under Illinois law, hearsay is generally inadmissible as evidence due to concerns about its reliability. However, there are numerous exceptions to this rule. For instance, statements made under the belief of impending death, statements against interest, and certain statements of personal or family history, among others, may be admissible. Additionally, there are statements that are not considered hearsay at all, such as admissions by a party-opponent. The Illinois Rules of Evidence, particularly Rule 801 which defines hearsay and its exceptions, and Rule 802 which addresses the hearsay rule, govern the admissibility of such statements. Attorneys must navigate these rules and relevant case law to determine whether a hearsay statement can be admitted in court.