What is the law on unanimity in a criminal trial where there is evidence that more than one crime occurred?

A unanimity instruction is required if there is evidence that more than one crime occurred, either of which could provide the basis for conviction under a single count. (See People v. Diedrich (1982) 31 Cal.3d 263, 281, 182 Cal.Rptr. 354, 643 P.2d 971 [when evidence suggested more than one act of bribery, jury must agree unanimously which act was the basis for conviction]; see People v. Beardslee (1991) 53 Cal.3d 68, 92, 279 Cal.Rptr. 276, 806 P.2d 1311 [A requirement of jury unanimity typically applies to acts that could have been charged as separate offenses].) On the other hand, the unanimity instruction is not required

[340 P.3d 323]

where multiple theories or acts may form the basis of a guilty verdict on one discrete criminal event. (Russo, supra, 25 Cal.4th at p. 1135, 108 Cal.Rptr.2d 436, 25 P.3d 641, italics added.) [W]here the evidence shows only a single discrete crime but leaves room for disagreement as to exactly how that crime was committed or what the defendant's precise role was, the jury need not unanimously agree on the basis or, as the cases often put it, the theory whereby the defendant is guilty. (Id. at p. 1132, 108 Cal.Rptr.2d 436, 25 P.3d 641.) This is true even if the two theories are based on different facts. (People v. Jenkins, supra, 22 Cal.4th at p. 1025, 95 Cal.Rptr.2d 377, 997 P.2d 1044 [unanimity instruction not required even where different facts would support aiding and abetting liability and liability as a direct perpetrator].)