What is the test for admitting prior testimony of an unavailable witness at a preliminary hearing?

"California permits the use of the prior testimony of a witness against a criminal defendant only when the unavailability of the witness and the reliability of the testimony are established. ( 686; Evid. Code, 1291, subd. (a)(2).)" (People v. Carter, supra, 36 Cal.4th at p. 1172.) "The testimony is deemed reliable if '[t]he party against whom the former testimony is offered was a party to the action or proceeding in which the testimony was given and had the right and opportunity to cross-examine the declarant with an interest and motive similar to that which he has at the hearing.' (Evid. Code, 1291, subd. (a) (2).)" (Ibid.) The preliminary hearing testimony of an unavailable witness may be admitted under these principles. (Id. at pp. 1172-1173.)