Does the hearsay rule apply to statements admitting gang membership?

hearsay rule, whether the witnesses were unavailable, and whether they qualify as case-specific facts. The trial court found the statements admitting gang membership fell within the exception to the hearsay rule for statements against their interests. Defendant argues that in the trial court, the People failed to prove the witnesses were unavailable, but this particular objection was not articulated in the trial court, so ordinarily we would not need to address that issue. (Evid. Code, 353; People v. Williams (2008) 43 Cal.4th 584, 620.) In any event, as we will demonstrate, because the "pattern of criminal gang activity" falls within the class of background evidence on which an expert may rely in forming an opinion notwithstanding its hearsay nature, any objection would have been properly overruled.