Is an expert entitled to offer an opinion about whether a crime that was committed would have been committed for the benefit of a criminal street gang?

Defendant "does not dispute that the expert was entitled to offer an opinion about whether a crime that was committed would have been committed for the benefit of a criminal street gang," rather, he contends that "the question posed by the prosecutor also called upon the expert to opine as to whether the hypothetical defendant 'was trying to intimidate the witnesses.' In other words, whether the defendant committed a crime." According to defendant, "This part of the question was tantamount to asking the expert whether the hypothetical defendant had committed the charged crime of attempt to dissuade a witness [citation], thereby violating the 'settled and long-established rule . . . that a witness cannot express an opinion concerning the guilt or innocence of the defendant.' (See People v. Clay (1964) 227 Cal.App.2d 87, 98-99)."

The prosecutor may ask an expert witness hypothetical questions based on the facts of a case, including questions that embrace the ultimate question of the defendant's guilt or innocence. (People v. Vang (2011) 52 Cal.4th 1038, 1048.) "[E]xpert testimony is permitted even if it embraces the ultimate issue to be decided. (Evid. Code, 805.) The jury still plays a critical role in two respects. First, it must decide whether to credit the expert's opinion at all. Second, it must determine whether the facts stated in the hypothetical questions are the actual facts, and the significance of any difference between the actual facts and the facts stated in the questions." (Id. at p. 1049-1050.) Accordingly, even assuming the hypothetical posed by the prosecutor called upon the expert to opine as to whether the hypothetical defendant was trying to intimidate the witnesses, as defendant contends, such opinion testimony was permissible. (Id. at p. 1048-1050.)