In People v. Chiu (2014) 59 Cal.4th 155, the defendant was found guilty of first degree murder committed with deliberation and premeditation, under a natural and probable consequences theory of aiding and abetting. (Chiu, supra, 59 Cal.4th at p. 158.) The Supreme Court granted review to determine whether the trial court erred in instructing that an accomplice could be found guilty of first degree murder if murder, rather than premeditated murder, was a natural and probable consequence. The court found an accomplice cannot be found guilty of "first degree premeditated murder under the natural and probable consequences doctrine." (Id. at pp. 158-159.) Previously, in People v. Favor (2012) 54 Cal.4th 868, the Supreme Court held an accomplice could be found guilty of attempted murder with premeditation where the jury instruction only referred to attempted murder, without reference to premeditation, as a natural and probable consequence. The Chiu court reasoned that premeditation for attempted murder was a penalty provision and not an element of the offense under section 664, subdivision (a). The Chiu court found Favor distinguishable in several respects: "the issue in the present case does not involve the determination of legislative intent as to whom a statute applies. Also, unlike Favor, which involved the determination of premeditation as a requirement for a statutory penalty provision, premeditation and deliberation as it relates to murder is an element of first degree murder. In reaching our result in Favor, we expressly distinguished the penalty provision at issue there from the substantive crime of first degree premeditated murder on the ground that the latter statute involved a different degree of the offense." (Chiu, supra, 59 Cal.4th at p. 163.) Instead, the court considered the common law basis of the natural and probable consequences doctrine. The court reasoned: "In the context of murder, the natural and probable consequences doctrine serves the legitimate public policy concern of deterring aiders and abettors from aiding or encouraging the commission of offenses that would naturally, probably, and foreseeably result in an unlawful killing." (Chiu, supra, 59 Cal.4th at p. 165.) However, this public policy is less apparent when applied to premeditated murder: "First degree murder, like second degree murder, is the unlawful killing of a human being with malice aforethought, but has the additional elements of willfulness, premeditation, and deliberation which trigger a heightened penalty. That mental state is uniquely subjective and personal. It requires more than a showing of intent to kill; the killer must act deliberately, carefully weighing the considerations for and against a choice to kill before he or she completes the acts that caused the death. Additionally, whether a direct perpetrator commits a nontarget offense of murder with or without premeditation and deliberation has no effect on the resultant harm. The victim has been killed regardless of the perpetrator's premeditative mental state. Although we have stated that an aider and abettor's 'punishment need not be finely calibrated to the criminal's mens rea' , the connection between the defendant's culpability and the perpetrator's premeditative state is too attenuated to impose aider and abettor liability for first degree murder under the natural and probable consequences doctrine, especially in light of the severe penalty involved and the above stated public policy concern of deterrence." (Id. at p. 166.) The court concluded that punishment for second degree murder was commensurate punishment for one who aids and abets a target crime that naturally and foreseeably results in a first degree premeditated murder. (Chiu, supra, 59 Cal.4th at p. 166.) However, the court also found an accomplice could still be found guilty of first degree murder for directly aiding and abetting a premeditated murder: "Because the mental state component-consisting of intent and knowledge--extends to the entire crime, it preserves the distinction between assisting the predicate crime of second degree murder and assisting the greater offense of first degree premeditated murder." (Id. at p. 167.) Because the court found a defendant could not be convicted of first degree premeditated murder under the natural and probable consequences doctrine, it had to determine whether giving the instructions allowing the jury to so convict the defendant was harmless error. (Chiu, supra, 59 Cal.4th at p. 167.) The court explained: "When a trial court instructs a jury on two theories of guilt, one of which was legally correct and one legally incorrect, reversal is required unless there is a basis in the record to find that the verdict was based on a valid ground. Defendant's first degree murder conviction must be reversed unless we conclude beyond a reasonable doubt that the jury based its verdict on the legally valid theory that defendant directly aided and abetted the premeditated murder. " (Ibid.) The court considered the record before it and found the jury might have based its first degree premeditated murder verdict on the natural and probable consequences theory. During trial, one of the jurors objected to the law on aiding and abetting. (Chiu, supra, 59 Cal.4th at p. 167.) The trial court questioned the juror, who stated she was bothered by the principle of aiding and abetting and putting the aider and abettor in the shoes of a perpetrator. The trial court removed the juror, replacing her with an alternate. The jury continued deliberating and found the defendant guilty of first degree premeditated murder. (Id. at p. 168.) The court concluded: "These events indicate that the jury may have been focusing on the natural and probable consequence theory of aiding and abetting and that the holdout juror prevented a unanimous verdict on first degree premeditated murder based on that theory. Thus, we cannot conclude beyond a reasonable doubt that the jury ultimately based its first degree murder verdict on a different theory, i.e., the legally valid theory that defendant directly aided and abetted the murder." (Ibid.)