In Davis v. Washington (2006) 547 U.S. 813, 817, the Supreme Court considered whether statements made to law enforcement personnel during a 911 call or at a crime scene are "testimonial" and thus subject to the requirements of the Sixth Amendment's Confrontation Clause. The court concluded that "statements are nontestimonial when made in the course of police interrogation under circumstances objectively indicating that the primary purpose of the interrogation is to enable police assistance to meet an ongoing emergency," but "they are testimonial when the circumstances objectively indicate that there is no such ongoing emergency, and that the primary purpose of the interrogation is to establish or prove past events potentially relevant to later criminal prosecution." (Id. at p. 822.) In Melendez-Diaz v. Massachusetts (2009) 557 U.S. 305, the United States Supreme Court addressed whether notarized certificates by lab analysts describing the existence and quantity of contraband (cocaine) in bags found in the defendant's possession were "testimonial," making their admission into evidence violative of the Confrontation Clause. The certificates were prepared nearly a week after the tests of the contraband were performed. (Id. at p. 315.) The court concluded that the certificates, which constituted affidavits, fell within the "'core class of testimonial statements'" proscribed by Crawford (Melendez-Diaz, supra, at p. 310), and that they were "functionally identical to live, in-court testimony, doing 'precisely what a witness does on direct examination.' " (Id. at pp. 310-311.) The court therefore held that "absent a showing that the analysts were unavailable to testify at trial and that the defendant had a prior opportunity to cross-examine them, the defendant was entitled to '"be confronted with"' the analysts at trial. " (Id. at p. 311, quoting Crawford, supra, 541 U.S. at p. 54.) In Bullcoming v. New Mexico (2011) 564 U.S. 131 S.Ct. 2705, the Supreme Court considered the admission of a laboratory report of a forensic analyst who tested the defendant's blood sample and certified that the blood alcohol concentration (BAC) in the sample was 0.21 grams per hundred milliliters, "an inordinately high level," which supported the defendant's conviction of aggravated drunk driving. (Id. at pp. 2710-2711.) The Supreme Court held that the admission of the report violated the Confrontation Clause because "the accused's right is to be confronted with the analyst who made the certification, unless that analyst is unavailable at trial, and the accused had an opportunity, pretrial, to cross-examine that particular scientist." (Id. at p. 2710.) In so holding, the court rejected the New Mexico Supreme Court's conclusion that the live testimony of another analyst satisfied the constitutional requirement of confrontation, noting that the testifying analyst, who had neither participated in nor observed the blood test "could not convey what the certifying tester knew or observed about the events his certification concerned, i.e., the particular test and testing process employed." (Id. at p. 2715.) Neither could the testifying analyst "expose any lapses or lies on the certifying analyst's part." (Ibid..) In Williams v. Illinois (2012) 567 U.S. 132 S.Ct. 2221, the Supreme Court considered a forensic DNA expert's testimony that included her reliance on a DNA profile from a rape victim produced by an outside laboratory in the expert's matching of that profile to a DNA profile the state laboratory produced from the defendant's blood sample. (Id. at pp. 2222-2223.) Justice Alito writing with the concurrence of three justices and with Justice Thomas concurring in the judgment, concluded that the expert's testimony did not violate the defendant's confrontation rights. The plurality held that the outside laboratory report, which was not admitted into evidence (id. at pp. 2230, 2235), was "basis evidence" to explain the expert's opinion, was not offered for its truth, and therefore did not violate the Confrontation Clause. (Id. at pp. 2239-2240.) The Supreme Court concluded further that, even had the report been offered for its truth, its admission would not have violated the Confrontation Clause, because the report was not a formalized statement made primarily to accuse a targeted individual. (Id. at pp. 2242-2244.) Applying an objective test in which the court looks "for the primary purpose that a reasonable person would have ascribed to the statement, taking into account all of the surrounding circumstances" (id. at p. 2243), the Court found that the primary purpose of the outside lab report "was to catch a dangerous rapist who was still at large, not to obtain evidence for use against the defendant, who was neither in custody nor under suspicion at that time." (Ibid.) Further, the Court found that no one at the outside laboratory could have possibly known that the profile it generated would result in inculpating the defendant, and there was therefore no prospect for fabrication and no incentive for developing something other than a scientifically sound profile. (Id. at pp. 2243-2244.) In Crawford v. Washington (2004) 541 U.S. 36, the Supreme Court considered the admissibility at trial of a tape-recorded statement made by the defendant's wife to police. Because the witness did not testify at trial due to a state marital privilege statute, the defendant argued that admission of his wife's out-of-court statement violated his federal constitutional right under the Sixth Amendment to confront witnesses offering testimony against him. (Id. at p. 40.) The Supreme Court agreed, stating that "testimonial statements of witnesses absent from trial may be admitted only where the declarant is unavailable, and only where the defendant has had a prior opportunity to cross-examine." (Id. at p. 59, fn. omitted.) The two-prong Crawford test of witness unavailability and prior opportunity to cross-examine applies only to statements that are "testimonial," not nontestimonial hearsay. (Crawford, supra, 541 U.S. at p. 68.) Although the Crawford court declined to "spell out a comprehensive definition of 'testimonial,'" it explained that "whatever else the term covers, it applies at a minimum to prior testimony at a preliminary hearing, before a grand jury, or at a former trial; and to police interrogations. These are the modern practices with closest kinship to the abuses at which the Confrontation Clause was directed." (Ibid.)