What is the test for evidence of past misconduct in a criminal case?

The rule is otherwise. "Although the trial court may in an appropriate case instruct sua sponte on the limited admissibility of evidence of past criminal conduct, we have consistently held that it is under no duty to do so." (People v. Collie (1981) 30 Cal.3d 43, 63, 177 Cal.Rptr. 458, 634 P.2d 534.) We are not persuaded that an exception is warranted in this case. Indeed, defendant's reason for offering evidence of his past misconduct was to persuade the jury that his present offense, like the earlier ones, was the product of his abuse of drugs. He invited the jury to consider those offenses in determining his guilt, and may not complain on appeal that it did so. (See People v. Williams (1988) 44 Cal.3d 883, 958-959, 245 Cal.Rptr. 336, 751 P.2d 395.)

2. Evidence of Mental State.