In People v. Genovese (2008) 168 Cal. App. 4th 817, three challenges to CC 571 were rejected. First, the court rejected a claim that the voluntary manslaughter instructions were erroneous because they did not tell the jury the role that malice or lack of malice plays in reducing murder to voluntary manslaughter. Genovese rejected the challenge, stating, “[t]he definition of malice may be interesting to lawyers and judges and law professors, but it does not aid the task of lay jurors to inform them that, when the defendant acts in an honest but unreasonable belief in the need to defend another, he is acting without malice.” (Ibid.)

The defense also argued that the trial court should have expressly instructed the jury that intent to kill or conscious disregard for life is an essential and required element of voluntary manslaughter. This claim was rejected because the instructions did let the jury know that a killing in imperfect self-defense (or heat of passion, etc.), whether intentional or in conscious disregard of life, is voluntary manslaughter. (Id. at 832.)

Finally, the defense contended that even if they found express or implied malice to exist, the jurors could still find defendant guilty of voluntary manslaughter if they believed that the defendant acted in heat of passion or in reasonable or unreasonable self-defense. The Court of Appeal concluded that the “defendant’s argument is defeated by the plain language of the instructions as given to the jury. [CC 571] states that ‘[a] killing that would otherwise be murder is reduced to voluntary manslaughter’ if defendant acted in imperfect defense of another or sudden quarrel or heat of passion.” (Ibid.)