Mil. R. Evid. 412 limits the extent to which an accused in a sexual assault case can introduce evidence
regarding the alleged victim’s prior sexual behavior. The rule, however, carves out three exceptions.
Under Mil. R. Evid. 412 (b)(1), the following evidence is admissible:
(A)evidence of specific instances of sexual behavior by the alleged victim offered to prove that a person other than the accused was the source of semen, injury, or other physical evidence;
(B)evidence of specific instances of sexual behavior by the alleged victim with respect to the person accused of the sexual misconduct offered by the accused to prove consent...; and
(C) evidence the exclusion of which would violate the constitutional rights of the accused. In analyzing admissibility, the military judge must first determine whether the evidence is relevant under Mil. R. Evid. 401, and then apply the balancing test under Mil. R. Evid. 412 (c)(3).
Under Mil. R. Evid. 412 (b)(1)(C), the accused has a right to present evidence that is relevant, material, and favorable to his defense. United States v. Banker, 60 M.J. 216 (C.A.A.F. 2004). In applying the rule, the military judge is not asked determine whether the proferred evidence is true, it is for the members to weigh the evidence and determine its
In determining whether evidence is material, the military judge looks at 'the importance of the issue for which the evidence was offered in relation to the other issues in the case; the extent to which this issue is in dispute; and the nature of the other evidence in the case pertaining to this issue. Banker, 60 M.J at 222 (quoting United States v. Colon-Angueira, 16 M.J. 20, 26 (C.M.A. 1983)). Under the rule, the term favorable is synonymous with “vital.” Id.
Evidence of an extramarital relationship can be relevant, material, and favorable to the defense theory of the case when it shows that the alleged victim would lie to protect the relationship. See generally, Olden v. Kentucky, 488 U.S. 227 6 (1988); United States v. Williams, 37 M.J. 352(C.M.A. 1993).
Evidence may also be constitutionally required when the alleged victim has a motive to testify falsely to explain to her boyfriend why she was with another individual. United States v. Sanchez, 44 M.J. 174, 179 (C.A.A.F. 1996).