A res gestae witness is an individual who has experienced an event firsthand and can therefore directly testify about what happened. The term derives from the Latin res gestae, meaning “things done.” Under the common law, res gestae witness testimony was inadmissible evidence as hearsay. For example, in Calderon v. O’Donahue, a 1891 Southern District of New York case, the Court ruled that where “a lawyer took a contract in his own name for the benefit of his client, anything which he may have said about the transaction to others, which was no part of it, is not admissible as part of the res gestae.”
However, in federal courts and in many state courts, specific rules on hearsay in evidentiary rules supplanted the common law hearsay rule making res gestae witness testimony inadmissible evidence. In many cases, the evidentiary rules substantially abrogated the common law rule and allowed res gestae witness testimony. For example, Federal Rule of Evidence Rule 803 specifically excludes certain res gestae witness testimony from hearsay, thereby making such evidence admissible. Rule 803(1) allows “[a] statement describing or explaining an event or condition, made while or immediately after the declarant perceived it” to be admissible; Rule 803(2) allows “[a] statement relating to a startling event or condition, made while the declarant was under the stress of excitement that it caused” to be admissible; and Rule 803(3) allows “[a] statement of the declarant’s then-existing state of mind (such as motive, intent, or plan) or emotional, sensory, or physical condition (such as mental feeling, pain, or bodily health), but not including a statement of memory or belief to prove the fact remembered or believed unless it relates to the validity or terms of the declarant’s will.”
[Last updated in April of 2021 by the Wex Definitions Team]