Is there any case law where evidence of prior criminal activity has been excluded as unduly prejudicial?

Even if we assume a relevance which we fail to perceive, the evidence would properly have been excludible as unduly prejudicial under the discretion allowed by Evidence Code, section 352. We have elsewhere recognized the substantial prejudicial effect inherent in evidence of prior offenses (People v. Haston (1968) supra, 69 A.C. 237, 251, 70 Cal.Rptr. 419, 444 P.2d 91), for which reason such evidence may be excluded despite apparent relevance. This case is a dramatic illustration of the prejudice that can be injected into a trial through the device of demonstrating prior criminal acts. By use of this stratagem, the prosecution was able to place before the jury the largely irrelevant but manifestly harmful information that

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