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 Arizona, hearsay is defined similarly to the federal rules, as an out-of-court statement offered in evidence to prove the truth of the matter asserted. Under Arizona law, hearsay is generally inadmissible unless it falls under one of the many exceptions. These exceptions are outlined in the Arizona Rules of Evidence, particularly in Rule 803 and Rule 804, which include circumstances such as present sense impressions, excited utterances, statements of mental, emotional, or physical condition, recorded recollections, records of regularly conducted activity, and statements under belief of impending death, among others. Additionally, some statements are not considered hearsay at all, such as a declarant-witness's prior statement if the declarant testifies and is subject to cross-examination about the prior statement, and admissions by a party-opponent. The Arizona Rules of Evidence are applied by Arizona courts, and the interpretation of these rules can be influenced by court opinions or cases that provide precedent on how the hearsay rule and its exceptions are to be applied in specific contexts.