¶1 Lindy Deer was convicted of third degree rape of a child after having sexual intercourse with a 15-year-old boy on multiple occasions. Deer claims that she was asleep during several acts of intercourse and *728cannot be guilty of rape because she did not act with volition. We hold that Deer’s claimed lack of volition amounts to an affirmative defense, for which the defendant bears the burden of proof by a preponderance of the evidence. The trial court correctly refused Deer’s request to instruct the jury that the State must prove beyond a reasonable doubt that she was awake during the acts at issue. We reverse the Court of Appeals.
FACTS
¶2 Lindy Deer, a 52-year-old woman, had sexual intercourse with 15-year-old R.R. on several occasions. Their relationship developed when R.R. moved in with his aunt in Auburn, Washington, to attend a private religious boarding school. Deer was an administrative assistant for R.R.’s aunt. Deer said she had “motherly” feelings for R.R., who would occasionally help her with chores and sleep over at her house. At one point, she gave R.R. “kissing lessons,” during which the two kissed on the mouth. 1 Report of Proceedings (RP) (2/11/09) at 24-25, 27-28. Deer told R.R. that she would have no problem having sex with him “if it wasn’t wrong in the eyes of society.” Id. at 39. The “kissing lessons” eventually escalated into a sexual relationship. R.R. later revealed their sexual relationship to a school guidance counselor, and Deer was arrested and charged with rape of a child in the third degree. The charging document alleged three counts, involving two discrete time periods: June 6-December 15, 2006 (Count I) and January 1-June 11, 2007 (Counts II & III). Clerk’s Papers (CP) at 64-65.
¶3 All told, between R.R.’s testimony and Deer’s, the jury heard evidence of at least seven separate incidents of sexual intercourse. At trial, Deer argued that some of her sexual acts were not voluntary, or “volitional,” because she was asleep when they occurred. Pursuant to this theory, she asked the trial judge to instruct the jury to acquit if there *729was reasonable doubt that sexual intercourse was volitional on her part. The trial judge refused, instead instructing the jury to acquit if Deer proved by a preponderance of the evidence that sex had occurred without her knowledge or consent. The jury was instructed that it needed to unanimously agree on one act for each count but did not need to find that all of the alleged acts occurred. Id. at 23. Deer acknowledged she was not asleep during all of the incidents. Additionally, during some of the incidents Deer testified she slept through, R.R. testified she was an active participant. Deer also testified that she did not consent to some of the incidents though she was aware they took place.
¶4 With respect to the jury instructions, Deer did not object to the “to convict” instructions for the three counts, which said nothing about “volition” as an element of the alleged crimes. Id. at 20-22. Deer refused the giving of any instruction on the defense of duress. 2 RP (2/12/09) at 3-5. Her only objection was to instruction 11, which set forth a defense based on the defendant’s lack of “knowledge or consent” to sexual intercourse. CP at 24. More specifically, Deer objected to placing upon her the burden of proving the defense by a preponderance of the evidence, but not to instructing the jury as to the meaning of “knowledge or consent.” 1 RP (2/12/09) at 111. Deer’s theory was that her lack of knowledge or consent was akin to a diminished capacity defense. Her counsel argued:
Your Honor, we believe this case is much more like diminished capacity in that you have to have some mental capacity to consent. We picture the State legislature finding a person guilty of a crime that they have no knowledge of even taking place at all.
Could we imagine an initiative of any kind where there is a proposal to pass law finding people guilty of crimes that they were even unaware that they participated in and I think the answer is no. This case is most like a diminished capacity.
Id. at 6-7.
*730¶5 While Deer apparently proposed an alternative instruction to instruction 11, based on language the State had agreed to, it is not in the record. At trial, Deer’s counsel described the instruction as stating that “volition goes to — really should go to reasonable doubt and if you have a reasonable doubt caused by lack of volition or evidence put on that we believe prove [s] lack of volition, that would go toward reasonable doubt, rather than a preponderance.” 2 RP (2/11/09) at 80. The State insists “the instruction that Deer proposed and the State agreed to would have required the defense to produce sufficient evidence to raise a reasonable doubt as to whether the acts of sexual intercourse were ‘volitional.’ RP (2/11/09-II) 78.” Suppl. Br. of Pet’r at 5 n.1. In the end, the State advocated for the court’s instruction 11, analogizing the defense of lack of volition to unwitting possession of contraband. 2 RP (2/12/09) at 3-5. Deer’s counsel lodged his objection. Id. at 111. The jury returned guilty verdicts on all three counts of child rape in the third degree, and the judge sentenced Deer to two 46-month sentences to be served concurrently.
¶6 The Court of Appeals set aside Deer’s conviction due to a charging error. State v. Deer, 158 Wn. App. 854, 861, 244 P.3d 965 (2010).1 Only because the issue could arise on remand did the Court of Appeals address Deer’s challenge to instruction 11. Id. at 862. The court held that the State was required to prove beyond a reasonable doubt that Deer’s actions were volitional, i.e., that she was awake during the encounters. Id. at 864. The State appealed and we granted review. State v. Deer, 171 Wn.2d 1012, 249 P.3d 1029 (2011). Thus, this case is in an unusual posture, as we are considering a claim of instructional error that has no practical effect on the validity of Deer’s conviction. We are therefore not concerned with whether any error was harmless in light of the way the case was charged and tried. The question is simply whether the State bears the burden of *731disproving Deer’s claim that she was asleep because volition is an element of every crime.2
ANALYSIS
¶7 The statute governing rape of a child in the third degree reads:
A person is guilty of rape of a child in the third degree when the person has sexual intercourse with another who is at least fourteen years old but less than sixteen years old and not married to the perpetrator and the perpetrator is at least forty-eight months older than the victim.
RCW 9A.44.079(1). The elements of the crime are thus (1) sexual intercourse with another (2) who is at least 14 years old but less than 16 years old and not married to the perpetrator and (3) the perpetrator is at least 48 months older than the victim. Due process requires the State to prove every element of a crime beyond a reasonable doubt. U.S. Const. amend. XIV; In re Winship, 397 U.S. 358, 364, 90 S. Ct. 1068, 25 L. Ed. 2d 368 (1970).
¶8 We generally consider a crime to be made up of two parts: (1) the actus reus and (2) the mens rea. State v. Eaton, 168 Wn.2d 476, 480, 229 P.3d 704 (2010). As a strict liability crime, child rape in the third degree requires no proof of mens rea. See State v. Chhom, 128 Wn.2d 739, 741-43, 911 P.2d 1014 (1996). Generally, the State must prove only that the act constituting a strict liability offense occurred. However, Deer argues that “ [a] s part of the actus reus of any crime, the State must prove beyond a reasonable doubt that a defendant voluntarily engaged in the proscribed conduct.” Suppl. Br. of Resp’t at 6. She claims that a perpetrator who was asleep during a criminal act has not voluntarily engaged in the prohibited act. Id. at 7-8. Deer *732urges this court to hold that once a defendant produces evidence of a lack of voluntary action, the State bears the burden of proving volition beyond a reasonable doubt. Id. at 9-11.3 In other words, Deer asks this court to hold, as the Court of Appeals did, that the State must prove beyond a reasonable doubt that she was awake when the acts of child rape took place.
¶9 Our review of this question reveals that little attention has been paid to the notion of actus reus, and courts and commentators find it difficult to draw a bright line between volition and the knowledge component of mens rea. A recent article advocating for treating volition as an element of the State’s case acknowledged that “ [n] otwithstanding the purportedly central role that actus reus inhabits in criminal law philosophy, it remains a relatively insignificant issue in case law,” and moreover, “courts are inconsistent on how they treat actus reus as an element.” Melissa Hamilton, Reinvigorating Actus Reus: The Case for Involuntary Actions by Veterans with Post-Traumatic Stress Disorder, 16 Berkeley J. Crim. L. 340, 348, 349 (2011). While the author lauds the Court of Appeals opinion in this case, and would rely on Winship, 397 U.S. 358, as a due process basis for treating volition as an element the State must establish, id. at 350, she recognizes that “contemporary criminal law appears to have deviated from the longstanding voluntary act doctrine.” Id. at 351.
¶10 The law has “deviated” for good reason; theory and practice sometimes diverge. Breaking criminal responsibility into its component parts of actus reus and mens rea is fine in theory, but requiring the prosecution to establish volition — here consciousness — as an “element” in the strict *733sense is unreasonable. Elements are the essential components of a criminal charge. The State bears the burden of proving each element beyond a reasonable doubt. The defendant bears no burden to disprove the elements of a crime. Upon pleading not guilty, the defendant cannot be compelled to produce evidence to disprove an element. The jury must be so instructed, and it was properly instructed in this case. Instruction 4 stated in relevant part:
The defendant has entered a plea of not guilty. That plea puts in issue every element of each crime charged. The State is the plaintiff and has the burden of proving each element of each crime beyond a reasonable doubt. The defendant has no burden of proving a reasonable doubt exists as to these elements.
CP at 17.
¶11 We must reject Deer’s contention that the State is required to prove as an element of child rape that she was awake during the alleged acts. While she is entitled to argue a lack of conscious action, her claim is properly treated as an affirmative defense, much like claims of involuntary intoxication, insanity, or unwitting possession. See 13B Seth A. Fine & Douglas J. Ende, Washington Practice: Criminal Law § 3204, at 237 (2d ed. 1998) (observing that for crimes in which there is no mens rea requirement, the defense of involuntary intoxication must be proved by the defendant by a preponderance of the evidence).4 The Court of Appeals recognized as much over 40 years ago in State v. Utter, 4 Wn. App. 137, 479 P.2d 946 (1971). There, the defendant claimed he did not commit a homicide because he killed the victim while acting under a “ ‘conditioned response’ ” resulting from his military training. Id. at *734139. The court cited numerous authorities recognizing that the theory of involuntary or automatistic acts is “similar to one of mental incapacity,” though “distinct from that concept.” Id. at 141. The distinction is that automatism does not involve any claim of mental disease sufficient to establish diminished capacity or insanity, and the theory provides a complete defense, not mitigation to a lesser offense. Id. Significantly, however, it is an affirmative defense: “ ‘Where, at the time of the killing, the slayer was clearly unconscious thereof, such unconsciousness will constitute a defense, as in the case of a homicide committed by one in a state of somnambulism, or while delirious from disease.’ ” Id. (quoting 1 Oscar Leroy Warren & Basil Michael Bilas, Warren on Homicide § 61, at 198-99 (perm. ed. 1938)); see also Utter, 4 Wn. App. at 143 (recognizing that “unconsciousness does not, in all cases provide a defense to a crime,” such as when it “is voluntarily induced through the use and consumption of alcohol or drugs”).
¶12 It is generally recognized that the defendant bears the burden of proving an affirmative defense by a preponderance of the evidence.5 The sole exception is when a defense “negates” an element of the charged offense, in which case due process requires the State to bear the burden of disproving the defense. State v. Lively, 130 Wn.2d 1, 10-11, 921 P.2d 1035 (1996). Deer’s “sleep sex” defense does not fall within the category of negating defenses. Third degree rape of a child is a strict liability offense, the elements of which are sexual intercourse, between the defendant and a child who is at least 14 but under 16 years of age and at least 48 months younger than the defendant, occurring in the state of Washington. A claim of having been asleep during sexual intercourse with a child does not negate the fact that sexual intercourse occurred.
*735¶13 The closest parallel to this defense may be the defense of unwitting possession in a prosecution for possession of a controlled substance. State v. Bradshaw, 152 Wn.2d 528, 98 P.3d 1190 (2004). Like rape of a child, possession of a controlled substance is a strict liability offense. Its elements are simply possession of an identified controlled substance in the state of Washington. See 11 Washington Practice: Washington Pattern Jury Instructions: Criminal 50.02, at 946 (3d ed. 2008). A defendant who asserts he did not know the substance was in his possession or did not know the nature of the substance must prove this by a preponderance of the evidence. Bradshaw, 152 Wn.2d at 538. The burden properly falls on the defendant because unwitting possession does not negate the fact of possession. Rather, as this court explained, “This affirmative defense ameliorates the harshness of a strict liability crime.” Id. Thus, the defense must be allowed in order to avoid an unjust conviction, but the defendant bears the burden of proving it.6
¶14 It makes no sense to depart from this allocation of the burden of proof when the defendant claims to have been asleep during a strict liability crime. Being asleep is one of the many reasons a person might assert she did not know the criminal act occurred. Consider how treating a state of sleep as a negating defense would play out with respect to unwitting possession. How is the defense different when *736the defendant claims he put on his roommate’s jacket without knowing drugs were in the pocket, versus when he asserts someone put the jacket on him while he was asleep? It does not take an overactive imagination to foresee the potential for confusion or even mischief. Beyond unwitting possession, it must be recognized that putting the burden on the State to disprove an assertion of unconsciousness may expand defenses in other areas, such as the crime of driving under the influence. See 32 Linda M. Callahan, Washington Practice: Washington DUI Practice Manual § 14:24, at 338 (2011-12 ed.) (noting Court of Appeals opinion in Deer “may be helpful in defending persons who are accused of DUI while under the influence of zolpidem, in that they were actually sleeping while committing the crime”).
¶15 The hypothetical example Deer offers to bolster her argument that the State bears the burden of proving consciousness actually disproves her point. Deer describes a case in which a 15-year-old boy drugs a 19-year-old woman and then has sexual intercourse with her while she is unconscious, making the woman potentially criminally liable under the statute at issue. Suppl. Br. of Resp’t at 16. Deer expresses concern that the woman would have to bear the burden of proof as to her involuntary participation, even though she is the victim and not the perpetrator of a crime. But the law contemplates this scenario. Deer’s example describes a textbook case of involuntary intoxication, which constitutes an allowable defense that “may absolve the defendant of any criminal responsibility.” State v. Hutsell, 120 Wn.2d 913, 920, 845 P.2d 1325 (1993); see also 13B Fine & Ende, supra, § 3204, at 237. Importantly, this defense must be proved by the defendant by the lower preponderance of the evidence standard. State v. Riker, 123 Wn.2d 351, 367, 869 P.2d 43 (1994) (citing State v. Gilcrist, 25 Wn. *737App. 327, 328-29, 606 P.2d 716 (1980)).7 In contrast, voluntary intoxication provides no defense to a strict liability crime insofar as it goes to the issue of mental state. State v. Swagerty, 60 Wn. App. 830, 833-34, 810 P.2d 1 (1991) (rejecting voluntary intoxication defense for rape of a child in the first degree).8 While we recognize that requiring any level of proof from a victim such as the one Deer describes is onerous, the reason for putting the burden of proof on the defendant in such cases is “because generally, affirmative defenses are uniquely within the defendant’s knowledge and ability to establish.” Riker, 123 Wn.2d at 367 (citing State v. Knapp, 54 Wn. App. 314, 320-22, 773 P.2d 134, review denied, 113 Wn.2d 1022 (1989)). We are not inclined to adopt a rule that contravenes the reasonable policy choice behind the allocation of burdens in these types of defenses.
¶16 The common thread among similar affirmative defenses counsels in favor of a consistent approach in allocating the burden of proof. Given that claims of unconsciousness are often connected with claims of intoxication, voluntary or involuntary, Deer’s approach would lead to inconsistency and confusion. If the defendant claims to have been unconscious because she was drugged, she bears the burden of proving the defense of involuntary intoxication by a preponderance of the evidence. If she claims her unconsciousness resulted from her voluntary use of drugs or alcohol, this provides no defense to a strict liability crime, as mental state is irrelevant. But, if she claims unconsciousness for no specified reason — she simply says, “I was asleep” — then under Deer’s argument the State bears the *738burden to disprove this assertion. We believe it makes more sense that the allowed defenses asserting unconsciousness be treated the same.9
¶17 The Court of Appeals did not address the similarity between Deer’s claim and intoxication defenses but instead relied on this court’s decision in Eaton, 168 Wn.2d 476. Deer, 158 Wn. App. at 862-65. Contrary to the Court of Appeals’ interpretation, Eaton does not support the conclusion that a “sleep sex” defense must be disproved by the prosecution. Eaton involved a sentencing enhancement under RCW 9.94A.533(5) for possession of a controlled substance inside a jail. The question was the proper interpretation of this statute, specifically whether a defendant could be held liable for this strict liability offense when the State was responsible for bringing him into the enhancement zone. The court interpreted the statute not to contemplate criminal liability in this situation.
[W]e attempt to construe statutes in a way that is consistent with their underlying purpose. [State v.] Crediford, 130 Wn.2d [747,] 755[, 927 P.2d 1129 (1996)]. As the Court of Appeals concluded, the State’s application of the enhancement statute would lead “to an unlikely, absurd, and strained consequence, imposing a strict liability sentence enhancement for involuntary possession of a controlled substance in a county jail or state correctional facility.” [State v.] Eaton, 143 Wn. App. [155,] 161[, 177 P.3d 157 (2008)]. Once Eaton was arrested, he no longer had control over his location. From the time of arrest, his movement from street to jail became involuntary: involuntary not because he did not wish to enter the jail, but because he was forcibly taken there by State authority. He no longer had the ability to choose his own course of action. Nor did he have the *739ability through some other course of action to avoid entering the area that would increase the penalty for the underlying crime. We doubt the legislature intended to grant the police such broad authority to affect the defendant’s punishment after arrest.
Eaton, 168 Wn.2d at 484-85 (footnote omitted).
¶18 Both the situation and the implications are different here. Liability for child rape is not “situational” in the way liability for being in an enhancement zone is (particularly when the defendant is under arrest and is transported into the enhancement zone by the State). See id. at 482. The concern in Eaton was the absurdity of interpreting RCW 9.94A.533(5) to impose liability for a circumstance within the State’s control, rather than the defendant’s. It is not at all clear that the holding in Eaton would extend beyond its unique facts — for example, to a situation in which the defendant claims he was asleep in a car that a friend drove into an enhancement zone.
¶19 The implications in this case are also different. The court in Eaton noted that the harm contemplated by enhancement zone statutes did not include the scenario in which the police were responsible for bringing a person possessing drugs into the zone. Id. at 485. In contrast, the harm contemplated by criminalizing rape of a child is precisely what occurred here: an adult had sexual intercourse with a child. The societal interest in preventing this harm is the same regardless of whether the defendant intended the harm or was even conscious it occurred. For this reason, Deer’s “sleep sex” defense is much more akin to defenses such as unwitting possession of drugs or involuntary intoxication. It admits the harmful act occurred but offers an excuse.10
*740¶20 Moreover, as with similar affirmative defenses, proof of the proposition, “I was asleep” is far more likely to be within the defendant’s knowledge and ability to establish. See Riker, 123 Wn.2d at 367. Deer herself recognizes this when she proposes that the burden of producing such evidence should be placed upon the defendant. Commentators have noted that claims of unconsciousness, somnambulism, and the like are unusual and somewhat counterintuitive and are best established by the party asserting them.
Involuntary conduct is a statistical and subjective abnormality; the relevant facts are peculiarly within the knowledge of the accused; and where a harm has been caused by a defendant’s act, it seems fair to require him to adduce evidence that the act was involuntary. This analysis suggests that for constitutional purposes involuntariness should be viewed as a general excuse rather than as a universal offense element.
2 Paul H. Robinson, Criminal Law Defenses § 171(d) at 266 (1984) (footnote omitted). The Court of Appeals in Utter observed that this is one of the reasons courts allow claims of automatism or involuntariness as a defense. The defense is so unusual that it undercuts criminal liability. See Utter, 4 Wn. App. at 141. But, this does not mean that involuntary conduct negates the commission of a strict liability crime. Rather, as we said in Bradshaw, a defense of involuntariness exists to “ameliorate [ ] the harshness of a strict liability crime.” Bradshaw, 152 Wn.2d at 538. In this instance, the burden of proof properly resides with the defendant.
CONCLUSION
¶21 While we appreciate the logical distinction between the actus reus and mens rea components of criminal liability, there is more to reason than logic. The guiding principle of reason in this case is that Deer’s claim of “sleep sex” is in reality an affirmative defense that does not negate any *741element of the strict liability crime of child rape. While a defendant must be allowed to argue that her actions were involuntary, thus excusing her from criminal liability, we hold that it is the defendant’s burden to prove this defense by a preponderance of the evidence. Accordingly, we reverse the Court of Appeals.
C. Johnson, Chambers, Owens, Fairhurst, and J.M. Johnson, JJ., concur. Madsen, C.J., concurs in the result only.The State did not seek review of that holding.
Like the Court of Appeals, we review this question because, although it is moot, it may arise on remand. Our resolution of this question will also provide guidance for future cases. See RAP 2.4(a); Westerman v. Cary, 125 Wn.2d 277, 286, 892 P.2d 1067 (1994).
The extent to which Deer is willing to accept a burden of producing evidence is not entirely clear. Deer raised a Fifth Amendment challenge in her pro se statement of additional ground for review in the Court of Appeals, challenging the trial court’s ruling that she would have to testify to establish her claim that R.R. sexually assaulted her. Moreover, as discussed below, if consciousness is truly an element of child rape, the general rule is that a defendant bears no burden— neither production nor persuasion — to disprove an element.
We note that involuntary intoxication is one kind of diminished capacity defense. 13B Fine & Ende, supra, § 3205, at 239. We have elsewhere suggested in dicta that a diminished capacity defense is a negating defense. See In re Estate of Kissinger, 166 Wn.2d 120, 129, 206 P.3d 665 (2009). This may be true of certain diminished capacity defenses that go to the mens rea of a crime. But there is no doubt that an involuntary intoxication defense puts the burden of persuasion, by a preponderance of the evidence, on the defendant.
This is not the same as creating a “reasonable doubt” as to an element of the State’s case, which is apparently what Deer’s proposed instruction would have required. See State v. Riker, 123 Wn.2d 351, 366-69, 869 P.2d 43 (1994).
The dissent fears that we read too much into Utter in coming to this conclusion, noting that Utter never specifies whether the lack of volition, as a defense, is an affirmative defense. Dissent at 746-48. But Utter certainly does not foreclose treating volition defenses as affirmative defenses and, as noted, common sense tells us that Deer’s “sleep sex” defense must be an affirmative defense. It admits the elements of the crime but offers an excuse from criminal liability. It may be that under Utter there are volitional defenses that are negating defenses. But this cannot be one of them. Neither does Utter undermine our conclusion when it observes that an unconscious act is not a criminal act, as the dissent argues. Id. at 747 (quoting Utter, 4 Wn. App. at 143). All Utter says is that an unconscious act “is merely a physical event or occurrence for which there can be no criminal liability” Utter, 4 Wn. App. at 143. We agree. The question here is who has the burden of proving there is no criminal liability. Nothing in Utter undercuts our conclusion that it is the defendant who properly bears the burden of proving her “sleep sex” defense.
Relatedly, if a defendant claims the ‘Victim” caused her to engage in sexual intercourse by threat or use of force, she may seek to prove the defense of duress by a preponderance of the evidence. See Riker, 123 Wn.2d at 366-67. As noted, Deer refused the giving of a duress instruction. 2 RP (2/12/09) at 3-5.
The court in Swagerty recognized that a defendant may still argue that a mental disease or defect rendered him unable to perceive the nature and quality of the act charged. 60 Wn. App. at 834. This analysis resonates with the analysis in Utter comparing the defense of automatism to insanity or diminished capacity. 4 Wn. App. at 141.
As noted, we are not insensitive to the concern that adult victims of juvenile crimes should not be prosecuted for offenses committed against them. But, the risk that an adult victim of rape will be wrongly prosecuted for child rape is minimized by the State’s statutory obligation to consider all of the evidence in a case, including affirmative defenses, before making a charging decision. RCW 9.94A.411. Thus, the situation here is not fundamentally different from other situations in which the defense bears the burden of proving an exculpatory defense and the State must consider the evidence relating to this defense before it brings any charges.
During trial, the State recognized that Deer’s defense would be a complete excuse to criminal liability. The prosecutor argued in closing that if Deer “was incapacitated, she would not be guilty” and if “she was actually forcibly raped by a person, obviously, there could be no criminal liability for it.” 2 RP (2/12/09) at 50.