Is a defendant permitted to stipulate to his status as an ex-felon to preclude introduction of evidence of his prior conviction?

Defendant contends that this ruling was error, relying on this court's decision in People v. Hall (1980) 28 Cal.3d 143, 167 Cal.Rptr. 844, 616 P.2d 826. Hall is not dispositive, however. In that case the defendant, an ex-felon, was charged with robbery and with violating section 12021, which prohibits possession of a concealable firearm by an ex-felon. He offered to stipulate to his status as an ex-felon, an element of the offense, and thereby preclude introduction of evidence of his prior conviction. The trial court refused to permit the stipulation, and evidence of a prior conviction for robbery was introduced. We held that this was error: "[I]f a defendant offers to admit the existence of an element of a charged offense, the prosecutor must accept that offer and refrain from introducing evidence of other crimes to prove that element to the jury." (28 Cal.3d 143, 152, 167 Cal.Rptr. 844, 616 P.2d 826.)