In People v. Barton (1995) 12 Cal.4th 186, the theory of defense was accident, the same defense presented here. Defendant Barton testified that the victim swung at him with a knife, ignored the defendant's demand to drop the knife, and then "made a sudden movement toward defendant, forcing him to step backward, at which time defendant's gun accidentally discharged." (Barton, supra, 12 Cal.4th at p. 202.) There was also evidence that the defendant repeatedly told the victim he would shoot if the victim did not drop the knife, the gun had a "medium pull," and the defendant was an experienced marksman. (Id. at pp. 202-203.) Over defense objection, the trial court instructed on imperfect self-defense voluntary manslaughter. (Ibid.) The California Supreme Court affirmed, observing that a reasonable jury could conclude from defendant's testimony that the defendant unreasonably believed the victim was armed and trying to attack him, and that defendant deliberately fired his gun in response to this perceived threat. (Id. at p. 202.)