Relevant evidence is admissible unless another rule of evidence, law, or valid principle mandates or permits exclusion.

United States v. Scheffer, 523 U.S. 303, pin? (1998).The exclusion of exculpatory evidence in a criminal trial does not violate the due constitutional right to present a defense if the grounds for exclusion are not arbitrary or disproportionate.

Fed. R. Evid. 801(a)(2) ("A "statement" is ... (2) nonverbal conduct of a person, if it is intended by the person as an assertion.).The nonverbal conduct of a person is a statement for purposes of the federal hearsay rule -- and thus can be hearsay -- only if the person who engages in the conduct intends his or her conduct to be an assertion.

Cf. Brown v. Keane, 355 F.3d 82, 90 (2d Cir. 2004) (holding, in a habeas corpus petition, that "the 911 tape, or at least the portion in which the caller state[d] that the light-skinned black men....If a statement is to fall within the hearsay exception for present sense impressions created by Federal Rule of Evidence 803(1) or a comparable State rule, the maker of the statement -- the declarant -- must personally perceive the event or condition that he or she describes or explains with the statement.