Tape-recorded police interviews are testimonial evidence and may not be admitted over defense objection. Police approached two witnesses to an assault and conducted taped interviews with them. One of those witnesses testified at the preliminary hearing and disavowed his statement to police. At trial, the prosecutor sought to introduce the tapes rather than calling the witnesses, because one of the witnesses would disavow the taped statement. The trial court permitted the introduction of the tapes. The Court of Appeal reversed, finding that the statements were testimonial and that the error was not harmless beyond a reasonable doubt.