How does expert testimony on BWS affect the credibility of a witness?

by providing the jury an explanation for the victims change in testimony. Id. at 1239. "As the [expert] witness told the jury, [BWS] is a psychological condition, which leads a female victim of physical abuse to accept her beatings because she believes that she is responsible for them, and hopes that by accepting one more beating, the pattern will stop." Id. at 1240. The expert testimony thus "provided the jury with information that would help it to determine which" version of the victims "testimony to credit." Id . Similarly, in the context of a child-abuse prosecution, we held that expert testimony on such abuse had "significant probative value in that it rehabilitated (without vouching for) the victims credibility after she was cross-examined about the reasons she delayed reporting and about the inconsistencies in her testimony." United States v. Bighead , 128 F.3d 1329, 1331 (9th Cir. 1997). Expert testimony on BWS could likewise rehabilitate the testimony of a domestic-abuse victim in cases of duress, regardless of whether she is the defendant or a government witness.