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 Colorado, hearsay is defined similarly to the federal standard, where it is considered an out-of-court statement offered in evidence to prove the truth of the matter asserted. Under Colorado law, hearsay is generally inadmissible unless it falls under one of the many exceptions. These exceptions are outlined in the Colorado Rules of Evidence, particularly in Rule 803 and Rule 804, which enumerate specific circumstances under which hearsay statements may be admissible, such as statements made under the belief of impending death, certain statements against interest, and records of regularly conducted activity, among others. Additionally, some statements are not considered hearsay at all, such as a declarant-witness's prior statement if the declarant testifies at the current trial or hearing and is subject to cross-examination. The Colorado courts interpret and apply these rules to determine the admissibility of hearsay in trials. Attorneys must navigate these rules and exceptions when considering the inclusion of hearsay evidence in their cases.