In my article Consent and Mistake of Fact as to Consent: Defenses to Adult Sexual Offenses under the Uniform Code of Military Justice, 2014 Emerging Issues 7277 (2014) (discussed here), I analyzed the difference between a defense and an affirmative defense:
There is a significant difference between a defense and an affirmative defense (also called a “special defense” in military practice). A defense denies commission of an act that constitutes an element of the charged offense. An affirmative defense does not “deny that the accused committed the objective acts constituting the offense charged [but instead] denies, wholly or partially, criminal responsibility for those acts.” R.C.M. 916(a). Put differently, a defense disproves an element while an affirmative defense addresses something that isn’t an element but nevertheless avoids criminal responsibility. For example, it is a defense that an accused did not kill a victim, while it is an affirmative defense that even though an accused did kill a victim, the killing was done in self-defense.
In a recent decision in United States v. Teague, __ M.J. __, No. 20140394 (A. Ct. Crim. App. Mar. 15, 2016) (link to slip op.), the Army CCA notes this difference in rejecting the appellant’s appellate claim that the Government failed to disprove the affirmative defense of mistake of fact as to consent to his conviction for sexual assault of an incapacitated person in violation of Article 120(b) (2012). However, the statute requires that the prosecution prove, as an element of the offense, that the incapacity of the victim be “known or reasonably should be known by the [accused].” Article 120(b)(3)(A). Accordingly:
If the government proves that an accused had actual knowledge that a victim was incapable of consenting, then, by definition, such an accused could not simultaneously honestly have believed that the victim consented. Similarly, if the government proves that an accused should have reasonably known that a victim was incapable of consenting, the government has also proven any belief of the accused that the victim consented was unreasonable.
Slip op. at 3. Put differently:
[A] mistake of fact defense is “baked in” to the elements of the offenses themselves. If, by way of example, the offense requires only that an accused commit a sexual act with someone who was incapable of consenting, it would be an affirmative defense that the accused honestly and reasonably believed the person was capable of consenting. By requiring the government prove that appellant knew, or reasonably should have known that AC was incapable of consenting, the government was required to disprove any defense of mistake of fact appellant may have had with regards to AC’s ability to consent.
Slip op. at 4. The CCA finds the evidence sufficient to sustain the appellant’s conviction.