Is a defendant's failure to object to the testimony of a gang expert forfeited on appeal?

Geier (2007) 41 Cal.4th 555, 609.) Thus, the claim is forfeited on appeal. (People v. Valdez (1997) 58 Cal.App.4th 494, 505 [failure to object to gang expert's testimony forfeits issue].)

Defendant's federal due process claim is forfeited for the same reason. In People v. Partida (2005) 37 Cal.4th 428, on which defendant relies, "a timely and specific objection to the admission of evidence was made on state law grounds. The issue was whether that objection was sufficient to preserve a federal due process claim where the due process claim was merely 'an additional legal consequence of the asserted [state] error . . . .' [Citation.] Here there was no specific or timely objection from which it could be argued that the constitutional claim flowed. Accordingly, we conclude that defendant's failure to object forfeits his [federal due process] claim on appeal." (People v. Geier, supra, 41 Cal.4th at pp. 610-611.)

In any event, defendant's argument has no merit. The trial court did not allow Sergeant Kain to "render the opinion that [ defendant] committed the crimes for the benefit of his gang." (Italics added.) Rather, Kain opined that a hypothetical crime benefited a hypothetical gang in several respects. "Even if expert testimony regarding the defendants themselves is improper, the use of hypothetical questions is proper." (People v. Vang (2011) 52 Cal.4th 1038, 1047, fn. 3 (Vang).)⁴

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