What is the current state of the law on the co-conspirator exception?

In United States v. Snow, 521 F.2d 730 (9th Cir.1975) we held that "otherwise inadmissible hearsay declarations of co-conspirators may be received into evidence when ... there is independent proof of the existence of the conspiracy and of the connection of the declarant and the defendant to it." Id. at 733.

At the time an objection was interposed concerning the admissibility of the entries as hearsay, the government did not suggest to the trial court that a proper foundation had been established under the co-conspirator exception. This theory was never advanced before the trial judge at any time during the trial. The trial court was not called upon to consider or to make any findings concerning the weight, sufficiency, and credibility of any foundational facts, independent of the expert's interpretation of the coded ledger entries, to prove the connection of the declarant to the conspiracy. Since this theory was not considered, we cannot now say that such evidence was not available. We decline to speculate on the state of this record that the trial court would have been satisfied that sufficient foundational facts were present to satisfy the co-conspirator exception, if the prosecutor had argued this theory in a timely manner. For us to sustain a theory of admissibility not presented below, would unfairly rob appellants of the opportunity to argue the weight, sufficiency and trustworthiness of the evidence to establish a proper foundation before the trial judge, or to offer proof to controvert the facts now relied upon by the government. See Giordenello v. United States, 357 U.S. 480, 488, 78 S.Ct. 1245, 1251, 2 L.Ed.2d 1503 (1957) (The government cannot support the admissibility of evidence on a theory raised for the first time on appeal because it would unfairly deprive the accused of an adequate opportunity to cross-examine the government's witnesses or adduce rebuttal evidence).

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