Admissibility of Evidence of a Person's Gang Affiliation in California
Evidence Code section 352 provides that a trial court may exclude evidence "if its probative value is substantially outweighed by the probability that its admission will . . . create substantial danger of undue prejudice, of confusing the issues, or of misleading the jury."
Evidence of a person's gang affiliation is admissible if it is relevant to prove a disputed issue and its probative value is not outweighed by its prejudicial effect. (People v. Champion (1995) 9 Cal.4th 879, 922-923; People v. Ruiz (1998) 62 Cal.App.4th 234, 239-240; People v. Olguin (1994) 31 Cal.App.4th 1355, 1369.)
However, evidence of gang affiliation should be excluded if it is only relevant to prove a defendant's criminal disposition. (Evid. Code, 1101, subd. (a); Champion, supra, at p. 913; Ruiz, supra, at p. 240.) Even if gang affiliation evidence is relevant, trial courts should closely scrutinize it because it "may have a highly inflammatory impact on the jury." (People v. Williams (1997) 16 Cal.4th 153, 193.)
If evidence of gang affiliation is only tangentially relevant, it ordinarily should be excluded because of its highly inflammatory impact. (People v. Cox (1991) 53 Cal.3d 618, 660; People v. Cardenas (1982) 31 Cal.3d 897, 904-905 (Cardenas).)
On appeal, the Court applies the abuse of discretion standard in reviewing a trial court's decision to overrule an Evidence Code section 352 objection and admit evidence. "The admission of gang evidence over an Evidence Code section 352 objection will not be disturbed on appeal unless the trial court's decision exceeds the bounds of reason." (People v. Olguin, supra, 31 Cal.App.4th at p. 1369.)