Is battered women's syndrome relevant in a murder case?

^2. "Battered women's syndrome evidence is generally relevant in murder cases in one of two different ways. First, it may be relevant to establish self-defense, i.e., that the defendant actually and reasonably believed in the need to defend against imminent death or serious bodily injury. [Citation.] Second, battered women's syndrome evidence may be relevant to establish 'imperfect self-defense,' i.e., that the defendant actually believed in the need to defend against imminent death or serious bodily injury, but the belief was objectively unreasonable. [Citations.] In both versions of self-defense, battered women's syndrome evidence may be relevant to establish 'defendant's actual, subjective perception that she was in danger and that she had to kill her husband to avoid that danger.' " (People v. Erickson (1997) 57 Cal.App.4th 1391, 1399.)