Bailey Wharton, Associate Member, University of Cincinnati Law Review
Introduction of battered woman syndrome evidence in a criminal defense is not a new phenomenon. In fact, it is very common and universally allowed in the context of self-defense when a woman attacks her abuser. However, there has been pushback from courts when it comes to the admissibility of battered woman syndrome evidence in the context of a duress defense. Currently, circuits courts are split on whether battered woman syndrome is even relevant in these cases.
This article will begin by briefly discussing the theory of battered woman syndrome and its application in criminal defenses, followed by a look at the two sides of the current circuit split—those that allow battered woman syndrome evidence in support of a duress defense and those that do not. Lastly, this article argues that the Fifth and Tenth circuit’s refusal to allow evidence and expert testimony on battered woman syndrome is unjust and highlights why allowing such evidence is imperative to a duress defense.
A. Battered Woman Syndrome and Its Use in Criminal Defenses
i. History of Battered Woman Syndrome
The theory of battered woman syndrome (“BWS”) was first introduced in the 1970s by psychotherapist Lenore Walker. This psychological theory describes a pattern of similar behavior or characteristics exhibited by women who have experienced a history of repeated physical, sexual, emotional, or psychological abuse at the hands of intimate or dominant male figures in their lives. The abuse is usually intended to “coerce her into doing whatever he wanted, without regard for her rights or feelings.” Walker posits two theories to explain the effects of BWS—the cycle theory of violence and the theory of learned helplessness. These theories help explain why BWS can alter a battered woman’s cognitive reactions to violence and abuse as well as their “perception of viable options for stopping the violence and abuse…[and] influences her future actions in response to violence.” As a result, “the perception or understanding of whether there are options available that would end the violence is based largely on what has actually been learned through experience.” While not every woman who has been a victim of long patterns of abuse will respond to threats or acts of violence in the same way, BWS theory encompasses a research and data-based, general characterization of behavior patterns followed by victims of BWS.
ii. Admissibility of Battered Woman Syndrome Evidence in Self-Defense and Duress Defenses
Expert testimony on BWS to support a defendants claim of self-defense is admissible universally in all courts and jurisdictions. However, despite the fact that both the self-defense and duress defenses include an objective reasonableness standard, courts have been more skeptical of allowing evidence of BWS to be admitted to support a duress defense.
Following the Fifth Circuit’s refusal to allow BWS evidence to support a duress defense in 1994 in United States v. Willis, there was an explosion of literature written in the years shortly after that disagreed with the outcome and argued that such evidence should be admissible in duress defenses in the same way as it has been allowed in self-defense cases. However, almost thirty years later, the federal circuit courts have yet to come to a consensus as to whether BWS evidence should be permitted to support a defense of duress.
III. Circuit Split
A circuit split exists regarding whether a criminal defendant may introduce expert testimony on or evidence of battered woman syndrome (or other psychological disorders like Post-Traumatic Stress Disorder (“PTSD”) that stem from a pattern of abuse) support a duress defense. The courts differ on whether BWS evidence is too subjective to be admissible evidence in supporting the objective duress defense standard.
In 1994, the Fifth Circuit unequivocally held that expert testimony on BWS is irrelevant and thus cannot be introduced to support a duress defense. However, in 2006, the Sixth Circuit held the opposite, finding that expert testimony on BWS is relevant and can provide the evidence needed to satisfy the elements of a duress defense, thus, creating the split. Since then, the D.C. Circuit, Ninth Circuit, and Seventh Circuit have all joined the Sixth Circuit in its holding and analysis. Only the Tenth Circuit has joined the Fifth Circuit in its holding that BWS expert testimony is admissible, but the courts differ on their reasoning.
A. Fifth and Tenth Circuit: Expert Testimony on Battered Woman Syndrome is Inadmissible
In United States v. Willis, the Fifth Circuit addressed BWS in relation to Willis’ duress defense against the charge of carrying a firearm during the commission of a drug trafficking crime. At trial, Willis called a clinical psychologist who testified about the historical pattern of abuse Willis had faced and that “Willis’ relationships fell into a clear pattern of a [BWS] and an abusive relationship.” However, the Fifth Circuit held that evidence of BWS is “inherently subjective” and thus, is not relevant in determining whether Willis acted under duress because “the classical elements of duress are stated in objective terms.” Such evidence does not address the objective inquiry of “whether a person of reasonable firmness would have succumbed to the level of coercion present in a given set of circumstances,” but rather “seeks to establish that, because of her psychological condition, [Willis] is unusually susceptible to the coercion. Further, the court explained that “to consider [BWS] evidence…would be to turn the objective inquiry that duress has always required into a subjective one,” and as such, is not relevant to and should not be allowed when determining criminal responsibility.
The Tenth Circuit, in United States v. Dixon, also held that evidence of BWS is not relevant to the objective reasonableness inquiry of a duress defense. The court held that the proposed duress defense jury instruction issued in this case required a strict objective reasonableness standard in which the court may only consider evidence of “external, concrete factors” that are unique to the defendant, not whether the defendant “has been influenced by non-tangible psychological conditions.” As a result, under the Pattern Jury Instruction proposed in this case, “the legal propriety of a defendant’s assessment of, and response to, the circumstances that allegedly have subjected [Dixon] to duress is determined by applying an objective lens.” The court further explained that the question of duress is what is “objectively reasonable—not what is reasonable only through the PTSD-distorted lens of Ms. Dixon.”
B. Sixth, Seventh, Ninth, and D.C. Circuit: Expert Testimony on Battered Woman Syndrome is Admissible
On the other hand, the Sixth, Seventh, Ninth, and D.C. Circuits disagree that such expert testimony does not address the objective reasonableness of the defendant’s behavior in accordance with the duress inquiry. In Dando v. Yukins, the Sixth Circuit held that evidence concerning BWS was not “at odds with a reasonableness requirement” due to the admissibility of such evidence in self-defense cases. The D.C. Circuit agreed in United States v. Nwoye. The court explained, “the duress defense requires a defendant to have acted reasonably under the circumstances, and expert testimony [of BWS] can help a jury assess whether a battered woman’s actions were reasonable.” In United States v. Lopez, the Ninth Circuit joined the Sixth and D.C. Circuits, adding that expert testimony on BWS is useful in determining the reasonableness of a defendant’s actions because “a defendant’s particular situation includes consideration of past experiences.” Most recently, the Seventh Circuit, in United States v. Dingwall, builds upon prior circuits’ reasoning by emphasizing that “expert evidence on battering and its effects may give a lay jury useful insights about the situation in which a person of reasonable firmness finds herself.”
IV. The Majority Split is the Just Approach
Not allowing a defendant to introduce expert testimony on BWS in support of her duress defense is unjust. It is imperative that courts allow expert testimony on the objective nature of BWS as it is “crucial to the juror’s ability to truly understand the defendant’s situation” and understand how BWS impacts the “reasonable perceptions of reality” of the defendant “based on the particular history of traumatic experience.” The cornerstone of a duress defense analysis is considering how a reasonable person “in [her] situation” would have responded.
The Fifth Circuit incorrectly categorized BWS testimony as “inherently subjective” and therefore automatically at odds with the reasonableness standard of a duress defense. This issue is not as cut and dry as the Fifth Circuit reasoned. It is necessary to allow defendants to introduce objective expert testimony of BWS. Unlike the Fifth Circuit boldly asserts, allowing BWS evidence does not turn the objective duress defense inquiry into a subjective inquiry. In fact, “such evidence may inform courts’ understanding of how a person may have perceived the situation without rendering that analysis subjective.” Allowing testimony on the “factual existence” and “objective traits” of BWS is relevant in providing the jury context of how a reasonable person, in the situation and circumstances experienced by the defendant, would respond. Inclusion of this type of evidence is particularly important in making sure the jury is informed “about the objective reasonableness of a person’s response, especially to unusual circumstances beyond the scope of a typical juror’s experience.”
Not allowing BWS and similar evidence in duress defense cases does a disservice to the jury—and the defendant—as the jury is not provided with the requisite information to guide them in how a reasonable person in the defendant’s situation would react; the jurors themselves may have no basis of understanding of how BWS impacts an abuse victim’s behavior. It is important and relevant for a jury to understand that “exposure to trauma, including violence and abuse, can change the way in which people view themselves, others, and the world.” In fact, victims of repeated abuse can “become incapable of recognizing opportunities for escape or other alternatives to their abusive environment…[and] such stress makes victims particularly sensitive to perceiving an imminent threat at the hands of their abuser, even when such a threat is not present.”
As a matter of fairness and justice, expert testimony on BWS should be broadly admissible in support of a duress defense. A defendant must have the opportunity to introduce the evidence, but the admissibility of the evidence must be contingent on it being an objective overview of the condition and relevant to proving the elements of a duress defense. The objective reasonableness inquiry of a duress defense “is not asked and answered in the abstract;” the jury must consider what a reasonable person in the defendant’s situation and circumstances would do. Therefore, evidence regarding the nature of BWS and the effects it has on victims is incredibly relevant in the jury’s assessment of the objective reasonableness of a defendant’s actions.
 See Christine Emerson, Note, United States v. Willis: No Room for the Battered Woman Syndrome in the Fifth Circuit?, 48 Baylor L. Rev. 317, 318 (1996).
 David L. Faigman & Amy J. Wright, The Battered Woman Syndrome in the Age of Science, 39 Ariz. L. Rev. 67, 68 (1997); Michaela Dunn, Subjective Vulnerabilities or Individualized Realities: The Merits of Including Evidence of Past Abuse to Support a Duress Defense, 54 Suffolk U. L. Rev. 347, 347-348 (2021).
 The term “Battered Woman Syndrome” is used rather than a more gender-neutral term such as “Battered Person Syndrome” (or “Battered Men Syndrome”) because while men are also abused by women, the “theory underlying the construct of BWS” has yet to be empirically studied in cases of abused men and “the psychological impact on the man does not appear to be consistent with trauma in most cases.” See Lenore E. A. Walker, The Battered Woman Syndrome 49-50 (4th ed. 2016), [https://perma.cc/K6E4-2QAU].
 Walker, supra note 5, at 50; Jessica Savage, Battered Woman Syndrome, 7 Geo. J. Gender & L. 761, 761 (2006); Emerson, supra note 1, at 320; Dunn, supra note 4, at 347.
 Walker, supra note 5, at 50.
 See Walker, supra note 5, at 94 (“[T]here are three distinct phases associated with a recurring battering cycle: (a) tension-building accompanied with rising sense of danger, (b) the acute battering incident, and (c) loving contrition.”). See also Meredith Blake, Coerced into Crime: The Application of Battered Woman Syndrome to the Defense of Duress, 9 Wis. Women’s L.J. 67, 71 (1994) (“It is this repetition of abuse and penitence that creates a condition of learned helplessness.”).
 Blake, supra note 8, at 71 (“A battered woman faces an often random and unpredictable pattern of abuse. Once a battered woman realizes that her behavior bears no relationship to the violence, she becomes demoralized and feels helpless. Repeated indiscriminate acts of violence contribute to a condition of learned helplessness, culminating with the woman’s belief that she is powerless to change or escape from her situation.”).
 Mary Ann Dutton, Understanding Women’s Responses to Domestic Violence: A Redefinition of Battered Woman Syndrome, 21 Hofstra L. Rev. 1191, 1219 (1993). See also Blake, supra note 8, at 71 (“The combination of the cycle of violence and the condition of learned helplessness, characteristic of so many battering relationships, has drastic effects upon the psyche of the battered woman.”).
 Dutton, supra note 10, at 1219.
 Walker, supra note 5, at 49. See generally Dutton, supra note 10, at 1225-1226 (“[B]attered women differ in the type and severity of their psychological reactions to violence and abuse, as well as in their strategies for responding to violence and abuse.”).
 See Tourlakis v. Morris, 738 F. Supp. 1128, 1128-1233 (S.D. Oh. 1990) (listing cases). See also Savage, supra note 6, at 763 n.22; cf. Savage, supra note 6, at 764 & n.23 (“[T]he admissibility of BWS evidence for self-defense claims has been codified by statute in numerous states.”).
 Emerson, supra note 1, at 318; Dunn, supra note 4, at 350; Blake, supra note 8, at 68; Kelly Grace Monacella, Supporting a Defense of Duress: The Admissibility of Battered Woman Syndrome, 70 Temp. L. Rev. 699, 700 (1997).
 See generally United States v. Willis, 38 F.3d 170 (5th Cir. 1994).
 See id. at 175, 177 (holding that BWS evidence does not address the objective inquiry of a duress defense, and therefore is not relevant “for the purposes of determining criminal responsibility.”).
 See Dando v. Yukins, 461 F.3d 791, 801, 802 (6th Cir. 2006) (holding that “the theory of Battered Woman’s Syndrome is not at odds with a reasonableness requirement” and that “[w]ith the help of an expert of Battered Woman’s Syndrome, Dando could have introduced evidence of all of the elements of a duress defense.”).
 See generally United States v. Nwoye, 824 F.3d 1129 (D.C. Cir. 2016); United States v. Lopez, 913 F.3d 807 (9th Cir. 2019); United States v. Dingwall, 6 F.4th 744 (7th Cir. 2021).
 See United States v. Dixon, 901 F.3d 1170, 1181-1182 (10th Cir. 2018) (holding that the language of the duress instruction did not offer “the same or similar invitation to consider evidence relating to conditions like PTSD” because it did not include the same “in his situation” language found in the Model Penal Code’s duress inquiry framework.”).
 See Willis, 38 F.3d at 173-174 (Willis “related that she greatly feared Perez because of the beatings she had received at his hands in the past…Willis argued that she believed that if she had protested when he put the gun in her purse, he would have beaten her right there in the restaurant…Willis contended that she did not knowingly, intentionally, or voluntarily carry or use the firearm, but rather did so only under duress.”).
 Id. at 174.
 Id. at 175.
 Id. at 176.
 United States v. Dixon, 901 F.3d 1170 (10th Cir. 2018).
 Id. at 1183.
 Id. at 1182.
 See Dando v. Yukins, 461 F.3d 791 (6th Cir. 2006); United States v. Dingwall, 6 F.4th 744 (7th Cir. 2021); United States v. Lopez, 913 F.3d 807 (9th Cir. 2019); United States v. Nwoye, 834 F.3d 1129 (D.C. Cir. 2016).
 Dando, 461 F.3d at 801.
 Id. (“[E]vidence of Battered Woman’s Syndrome could be introduced to the jury “because it relates to the question whether she reasonably believed her life was in danger.”) (quoting People v. Wilson, 194 Mich. App. 599, 602 (Mich. Ct. Ap. 1992)).
 824 F.3d at 1136.
 913 F.3d at 822.
 6 F.4th 744, 747 (7th Cir. 2021).
 Emerson, supra note 1, at 320.
 Dutton, supra note 10, at 1219.
 Dutton, supra note 10, at 1219.
 Model Penal Code § 2.09(1) (Am. Law. Inst. 1985) (emphasis added).
 United States v. Dingwall, 6 F.4th 744, 755 (7th Cir. 2021).
 Id. at 755.
 Emerson, supra note 1, at 319.
 Dingwall, 6 F.4th at 756-757.
 Dutton, supra note 10, at 1218
 Dunn, supra note 4, at 348.
 Dingwall, 6 F.4th at 755; United States v. Nwoye, 824 F.3d 1129, 1136 (D.C. Cir. 2016).
 Dingwall, 6 F.4th at 754.