What is the consequence of an error by a jury in the trial of defendant in his murder case?

On any standard, we do not find this error to be harmless. As noted above, on the evidence presented, the jury could reasonably have concluded that defendant's conduct went beyond that necessary to commit the underlying crime of attempted robbery and was reasonably likely to provoke a lethal response from Arreola. But it might also have concluded otherwise, absent the instructional error. As such, it is reasonably probable that a result more favorable to defendant would have been reached in the absence of the error. (See People v. Watson (1956) 46 Cal.2d 818, 836.) For the same reason, we cannot confidently say the error was harmless beyond a reasonable doubt. (See Chapman v. California (1967) 386 U.S. 18, 24.)

We conclude the instructional error requires reversal of defendant's murder conviction.

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