Smith v. Arizona, 602 U.S. ___ (2024) (2024)

NOTICE: This opinion is subject toformal revision before publication in the United States Reports.Readers are requested to notify the Reporter of Decisions, SupremeCourt of the United States, Washington, D.C. 20543,pio@supremecourt.gov, of any typographical or other formalerrors.SUPREME COURT OF THE UNITED STATES_________________No. 22–899_________________JASON SMITH, PETITIONER v. ARIZONAon writ of certiorari to the court of appealsof arizona, division one[June 21, 2024]Justice Kagan delivered the opinion of theCourt.The Sixth Amendment’s Confrontation Clauseguarantees a criminal defendant the right to confront the witnessesagainst him. The Clause bars the admission at trial of “testimonialstatements” of an absent witness unless she is “unavailable totestify, and the defendant ha[s] had a prior opportunity” tocross-examine her. Crawford v. Washington, 541 U.S.36, 53–54 (2004). And that prohibition applies in full toforensic evidence. So a prosecutor cannot introduce an absentlaboratory analyst’s testimonial out-of-court statements to provethe results of forensic testing. See Melendez-Diaz v.Massachusetts, 557 U.S.305, 307, 329 (2009).The question presented here concerns theapplication of those principles to a case in which an expertwitness restates an absent lab analyst’s factual assertions tosupport his own opinion testimony. This Court has held that theConfrontation Clause’s requirements apply only when the prosecutionuses out-of-court statements for “the truth of the matterasserted.” Crawford, 541 U.S., at 60, n.9. Somestate courts, including the court below, have held that thiscondition is not met when an expert recites another analyst’sstatements as the basis for his opinion. Today, we reject thatview. When an expert conveys an absent analyst’s statements insupport of his opinion, and the statements provide that supportonly if true, then the statements come into evidence for theirtruth. As this dispute illustrates, that will generally be the casewhen an expert relays an absent lab analyst’s statements as part ofoffering his opinion. And if those statements are testimonialtoo—an issue we briefly address but do not resolve as to thiscase—the Confrontation Clause will bar their admission.IAThe Confrontation Clause provides that “[i]nall criminal prosecutions, the accused shall enjoy the right... to be confronted with the witnesses against him.”In operation, the Clause protects a defendant’s right ofcross-examination by limiting the prosecution’s ability tointroduce statements made by people not in the courtroom. For atime, this Court held that the Clause’s “preference forface-to-face” confrontation could give way if a court found that anout-of-court statement bore “adequate indicia of reliability.”Ohio v. Roberts, 448 U.S.56, 65–66 (1980). But two decades ago, the Court changedcourse, to better reflect original understandings. InCrawford v. Washington, the Court deemed it“fundamentally at odds with the right of confrontation” to admitstatements based on judicial determinations of reliability. 541U.S., at 61. The Clause, Crawford explained,“commands[] not that evidence be reliable, but thatreliability be assessed in a particular manner: by testing in thecrucible of cross-examination.” Ibid. And so the Clause barsthe admission at trial of an absent witness’s statements—howevertrustworthy a judge might think them—unless the witness isunavailable and the defendant had a prior chance to subject her tocross-examination.But not always. The Clause’s prohibition“applies only to testimonial hearsay”—and in that two-word phraseare two limits. Davis v. Washington, 547 U.S.813, 823 (2006). First, in speaking about “witnesses”—or “thosewho bear testimony”—the Clause confines itself to “testimonialstatements,” a category whose contours we have variously described.Id., at 823, 826; see id., at 822 (statements “madein the course of police interrogation” were testimonial when “theprimary purpose of the interrogation [was] to establish or provepast events potentially relevant to later criminal prosecution”);Michigan v. Bryant, 562 U.S.344, 358, 359 (2011) (statements made to police “to meet anongoing emergency” were “not procured with a primary purpose ofcreating an out-of-court substitute for trial testimony”);Melendez-Diaz, 557 U.S., at 311 (testimonialcertificates of the results of forensic analysis were created“under circ*mstances which would lead an objective witnessreasonably to believe that the statement[s] would be available foruse at a later trial”); infra, at 19. Second and morerelevant here, the Clause bars only the introduction ofhearsay—meaning, out-of-court statements offered “to prove thetruth of the matter asserted.” Anderson v. UnitedStates, 417 U.S.211, 219 (1974). When a statement is admitted for a reasonunrelated to its truth, we have held, the Clause’s “role inprotecting the right of cross-examination” is not implicated.Tennessee v. Street, 471 U.S.409, 414 (1985); see Anderson, 417 U.S., at 220.That is because the need to test an absent witness ebbs when hertruthfulness is not at issue. See ibid.; Street, 471U.S., at 414; infra, at 13–14, 17.Not long after Crawford, the Court madeclear that the Confrontation Clause applies to forensic reports. InMelendez-Diaz v. Massachusetts, state prosecutorsintroduced “certificates of analysis” (essentially, affidavits)stating that lab tests had identified a substance seized from thedefendant as cocaine. 557 U.S., at 308. But the State did notcall as witnesses the analysts who had conducted the tests andsigned the certificates. We held that a “straightforwardapplication” of Crawford showed a constitutional violation.557 U.S., at 312. The certificates were testimonial: They hadan “evidentiary purpose,” identical to the one served had theanalysts given “live, in-court testimony.” Id., at 311. Andthe certificates were offered to prove the truth of what theyasserted: that the seized powder was in fact cocaine. Seeid., at 310–311. So the defendant had a right tocross-examine the lab-analyst certifiers. In reaching thatconclusion, we rejected the State’s claim that the results ofso-called “neutral, scientific testing” should be subject to adifferent rule. Id., at 317. We again underscored that theConfrontation Clause commanded not reliability but one way oftesting it—through cross-examination. See ibid. And wethought that method might have plenty to do in cases involvingforensic analysis. After all, lab tests are “not uniquely immunefrom the risk of manipulation” or mistake. Id., at 318. Thedefendant might have used cross-examination to probe “what teststhe analysts performed,” whether those tests “present[ed] a risk oferror,” and whether the analysts had the right skill set to“interpret[] their results.” Id., at 320.Two years later, the Court relied onMelendez-Diaz to hold that a State could not introduce onelab analyst’s written findings through the testimony of another. InBullcoming v. New Mexico, 564U.S. 647, 651–652 (2011), an analyst tested the blood-alcohollevel of someone charged with drunk driving, and prepared a“testimonial certification” reporting that the level was higherthan legal. But by the time the driver’s trial began, that analysthad been placed on unpaid leave. So the State instead called adifferent analyst from the same lab to testify as to what thecertification said. The substitute analyst had similarqualifications, and knew about the type of test performed. But theCourt held that insufficient to satisfy the Confrontation Clause.The “surrogate testimony,” the Court explained, “could not conveywhat [the certifying analyst] knew or observed” about “theparticular test and testing process he employed.” Id., at661. Nor could that “testimony expose any lapses or lies on thecertifying analyst’s part,” or offer any insight into whether hisleave-without-pay was the result of misconduct. Id., at 662.Concluded the Court: “[W]hen the State elected to introduce [the]certification,” its author—and not any substitute—“became [the]witness [that the defendant] had the right to confront.”Id., at 663.The very next Term brought another case in whichone lab analyst related what another had found—though this time onthe way to stating her own conclusion. In Williams v.Illinois, 567 U.S.50 (2012), state police sent vagin*l swabs from a rape victimknown as L.J. to a private lab for DNA testing. When the labsent back a DNA profile, a state analyst checked it against thepolice department’s database and found that it matched the profileof prior arrestee Sandy Williams. The State charged Williams withthe rape, and he went to trial. The prosecution chose not to bringthe private lab analyst to the stand. Instead, it called SandraLambatos, the state analyst who had searched the police databaseand found the DNA match. Lambatos had no first-hand knowledge ofhow the private lab had produced its results; she did not even knowwhether those results actually came from L. J.’s vagin*l swabs (asopposed to some other sample). But she spoke repeatedly aboutcomparing Williams’s DNA to the DNA “found in [L.J.’s]vagin*l swabs.” Id., at 61, 71 (plurality opinion); seeid., at 124 (Kagan, J., dissenting). So in addition todescribing how she discovered a match, Lambatos became the conduitfor what a different analyst had reported—that a particular DNAprofile came from L.J.’s vagin*l swabs. Williams objected, attrial and later: He thought that, just as in Bullcoming,crucial evidence had been admitted through a surrogate expert, thusviolating his right of confrontation.But the Illinois Supreme Court rejectedWilliams’s claim, holding that Lambatos’s testimony about theprivate lab analyst’s finding did not raise a Confrontation Clauseissue. See People v. Williams, 238 Ill. 2d 125,143–144, 939 N.E.2d 268, 278–279 (2010). The court explained thatunder state evidence law, an expert can disclose “underlying factsand data” for “the purpose of explaining the basis for [her]opinion.” Id., at 137, 143, 939 N.E. 2d, at 274–275,278. And when she does so, the court held, the testimony is notsubject to the Confrontation Clause because it is not admitted “forthe truth of the matter asserted.” Id., at 143, 939N.E. 2d, at 278. Thus, Lambatos could relay the private lab’sfinding that L.J.’s vagin*l swabs produced a certain DNAprofile in order to “explain[] the basis for her opinion”that “there was a DNA match between [Williams’s] blood sample andthe sem*n sample recovered from L.J.” Id., at 150, 939N.E. 2d, at 282. The admission of the private lab report’scontents for that “limited purpose,” the court reasoned, would “aidthe [factfinder] in assessing the value of [Lambatos’s] opinion.”Id., at 144, 939 N.E. 2d, at 278; see id., at150, 939 N.E. 2d, at 282.This Court granted Williams’s petition forcertiorari, but failed to produce a majority opinion. Four Membersof the Court approved the Illinois Supreme Court’s approach to“basis evidence,” and agreed that Lambatos’s recitation of theprivate lab’s findings served “the legitimate nonhearsay purpose ofilluminating the expert’s thought process.” Williams, 567U.S., at 78 (plurality opinion). But the remaining fiveMembers rejected that view. Those five stated, in two opinions,that basis evidence is generally introduced for its truth, and wasso introduced at Williams’s trial. Justice Thomas explained that“the purportedly limited reason for [the basis] testimony—to aidthe factfinder in evaluating the expert’s opinion—necessarilyentail[ed] an evaluation of whether [that] testimony [was] true”:“[T]he validity of Lambatos’[s] opinion ultimately turned on thetruth of [the private lab analyst’s] statements.” Id., at106, n.1, 108 (concurring in judgment). A dissent for anotherfour Justices agreed: “[T]he utility of the [private analyst’s]statement that Lambatos repeated logically depended on its truth.”Id., at 132 (opinion of Kagan, J.). And the State could notavoid that conclusion by “rely[ing] on [Lambatos’s] status as anexpert.” Id., at 126. Those shared views might have made fora happy majority, except that a different Confrontation Clauseissue intruded. Justice Thomas thought that the private lab reportwas not testimonial because it lacked sufficient formality, soaffirmed the Illinois Supreme Court on that alternative ground. Thebottom line was that Williams lost, even though five Members ofthis Court rejected the state court’s “not for the truth”reasoning.[1]Our opinions in Williams “have sownconfusion in courts across the country” about the ConfrontationClause’s application to expert opinion testimony. Stuart v.Alabama, 586 U.S. ___, ___ (2018) (Gorsuch, J.,dissenting from denial of certiorari) (slip op., at 2). Some courtshave applied the Williams plurality’s “not for the truth”reasoning to basis testimony, while others have adopted the opposedfive-Justice view.[2] This caseemerged out of that muddle.BLike Melendez-Diaz, this case involvesdrugs. In December 2019, Arizona law enforcement officers executeda search warrant on a property in the foothills of Yuma County.Inside a shed on the property, they found petitioner Jason Smith.They also found a large quantity of what appeared to be drugs anddrug-related items. As a result, Smith was charged with possessingdangerous drugs (methamphetamine) for sale; possessing marijuanafor sale; possessing narcotic drugs (cannabis) for sale; andpossessing drug paraphernalia. He pleaded not guilty, and the casewas set for trial.In preparation, the State sent items seized fromthe shed to a crime lab run by the Arizona Department of PublicSafety (DPS) for a “full scientific analysis.” App. to Pet. forCert. 127a. The State’s request identified Smith as the individual“associated” with the substances, listed the charges against him,and noted that “[t]rial ha[d] been set.” Ibid. AnalystElizabeth Rast communicated with prosecutors about exactly whichitems needed to be examined, and then ran the requested tests. Seeid., at 99a.Rast prepared a set of typed notes and a signedreport, both on DPS letterhead, about the testing. The notesdocumented her lab work and results. They disclosed, for each ofeight items: a “[d]escription” of the item; the weight of the itemand how the weight was measured; the test(s) she performed on theitem, including whether she first ran a “[b]lank” on the testingequipment; the results of those tests; and a “[c]onclusion” aboutthe item’s identity. See id., at 88a–98a. The signed reportthen distilled the notes into two pages of ultimate findings,denoted “results/interpretations.” See id., at 85a–87a.After listing the eight items, the report stated that four“[c]ontained a usable quantity of methamphetamine,” three“[c]ontained a usable quantity of marijuana,” and one “[c]ontaineda usable quantity of cannabis.” Id., at 86a–87a. The Stateoriginally planned for Rast to testify about those matters atSmith’s trial.But with three weeks to go, the State called anaudible, replacing Rast with a different DPS analyst as its expertwitness. In the time between testing and trial, Rast had stoppedworking at the lab, for unexplained reasons. And the State chosenot to rely on the now-former employee as a witness. So theprosecutors filed an amendment to their “final pre-trial conferencestatement” striking out the name Elizabeth Rast and adding“Greggory Longoni, forensic scientist (substitute expert).”Id., at 26a. Longoni had no prior connection to the Smithcase, and the State did not claim otherwise. Its amendment simplystated that “Mr. Longoni will provide an independent opinion on thedrug testing performed by Elizabeth Rast.” Ibid. And itcontinued: “Ms. Rast will not be called. [Mr. Longoni] is expectedto have the same conclusion.” Ibid.And he did come to the same conclusion, inreliance on Rast’s records. Because he had not participated in theSmith case, Longoni prepared for trial by reviewing Rast’s reportand notes. And when Longoni took the stand, he referred to thosematerials and related what was in them, item by item by item. As toeach, he described the specific “scientific method[s]” Rast hadused to analyze the substance (e.g., a microscopicexamination, a chemical color test, a gas chromatograph/massspectrometer test). Id., at 41a; see id., at 42a,46a–48a. And as to each, he stated that the testing had adhered to“general principles of chemistry,” as well as to the lab’s“policies and practices,” id., at 47a–48a; see id.,at 40a; so he noted, for example, that Rast had run a “blank” toconfirm that testing equipment was not contaminated, id., at42a, 47a. After thus telling the jury what Rast’s records conveyedabout her testing of the items, Longoni offered an “independentopinion” of their identity. Id., at 46a–47a, 49a. Morespecifically, the opinions he offered were: that Item 26 was “ausable quantity of marijuana,” that Items 20A and 20B were “usablequantit[ies] of methamphetamine,” and that Item 28 was “[a] usablequantity of cannabis.” Ibid.After Smith was convicted, he brought an appealfocusing on Longoni’s testimony. In Smith’s view, the State’s useof a “substitute expert”—who had not participated in any of therelevant testing—violated his Confrontation Clause rights.Id., at 26a; see Brief for Appellant Smith in No. 1 CA–CR21–0451 (Ariz. Ct. App.), pp.20–23. The real witness againsthim, Smith urged, was Rast, through her written statements; but hehad not had the opportunity to cross-examine her. See ibid.The State disagreed. In its view, Longoni testified about “his ownindependent opinions,” even though making use of Rast’s records.Brief for Appellee Arizona in No. 1 CA–CR 21–0451 (Ariz. Ct. App.),p.22. So Longoni was the only witness Smith had a right toconfront. See ibid.The Arizona Court of Appeals affirmed Smith’sconvictions, rejecting his Confrontation Clause challenge. Itrelied on Arizona precedent (similar to the Illinois SupremeCourt’s decision in Williams) stating that an expert maytestify to “the substance of a non-testifying expert’s analysis, ifsuch evidence forms the basis of the [testifying] expert’sopinion.” App. to Pet. for Cert. 11a–12a (quoting Stateexrel. Montgomery v. Karp, 236 Ariz. 120, 124, 336P.3d 753, 757 (App. 2014)). That is because, the Arizona courtshave said, the “underlying facts” are then “used only to show thebasis of [the in-court witness’s] opinion and not to prove theirtruth.” Ibid., 336 P.3d, at 757. On that view, theCourt of Appeals held, Longoni could constitutionally“present[] his independent expert opinions” as “based on hisreview of Rast’s work.” App. to Pet. for Cert. 11a.We granted certiorari to consider thatreasoning, 600 U.S. ___ (2023), and we now rejectit.[3]IISmith’s confrontation claim can succeed onlyif Rast’s statements came into evidence for their truth. As earlierexplained, the Clause applies solely to “testimonialhearsay.” Davis, 547 U.S., at 823 (emphasisadded); see supra, at 3. And that means the Clause “does notbar the use of testimonial statements for purposes other thanestablishing the truth of the matter asserted.” Crawford,541 U.S., at 60, n.9. So a court analyzing aconfrontation claim must identify the role that a givenout-of-court statement—here, Rast’s statements about her labwork—served at trial. On that much, indeed, the entireWilliams Court agreed. Amid all the fracturing that caseproduced, every Justice defined its primary question in the sameway: whether the absent analyst’s statements were introduced fortheir truth. See 567 U.S., at 57–58 (plurality opinion);id., at 104 (Thomas, J., concurring in judgment);id., at 125–126 (Kagan, J., dissenting). The parties herelikewise concur in that framing. See Brief for Smith 28–29; Brieffor Arizona 17–18. If Rast’s statements came in to establish thetruth of what she said, then the Clause’s alarms begin to ring; butif her statements came in for another purpose, then those alarmsfall quiet.Where the parties disagree, of course, is inanswering that purpose question. Smith argues that the “for thetruth” condition is satisfied here, just as much as inMelendez-Diaz or Bullcoming. See Brief for Smith23–28; supra, at 3–5. In his view, Rast’s statements wereconveyed, via Longoni’s testimony, to establish that what she saidhappened in the lab did in fact happen. Or put more specifically,those statements were conveyed to show that she used certainstandard procedures to run certain tests, which enabledidentification of the seized items. The State sees the matterdifferently. See Brief for Arizona 19–26. Echoing the Arizona Courtof Appeals (and the Illinois Supreme Court in Williams), theState argues that Rast’s statements came into evidence not fortheir truth, but instead to “show the basis” of the in-courtexpert’s independent opinion. Brief for Arizona 21; seesupra, at 6. And to defend that characterization, Arizonaemphasizes that its Rule of Evidence 703 (again, like Illinois’s)authorizes the admission of such statements only for thatpurpose—i.e., to “help[] the jury [to] evaluate” theopinion testimony. Brief for Arizona 20–21; see post, at 8(Alito, J., concurring in judgment) (arguing the same as to FederalRule of Evidence 703).Evidentiary rules, though, do not control theinquiry into whether a statement is admitted for its truth. Thatinquiry, as just described, marks the scope of a federalconstitutional right. See supra, at 11. And federalconstitutional rights are not typically defined—expanded orcontracted—by reference to non-constitutional bodies of law likeevidence rules.[4] Theconfrontation right is no different, as Crawford made clear.“Where testimonial statements are involved,” that Court explained,“the Framers [did not mean] to leave the Sixth Amendment’sprotection to the vagaries of the rules of evidence.” 541U.S., at 61. Justice Thomas reiterated the point inWilliams: “[C]oncepts central to the application of theConfrontation Clause are ultimately matters of federalconstitutional law that are not dictated by state or federalevidentiary rules.” 567 U.S., at 105 (opinion concurring injudgment). We therefore do not “accept [a State’s] nonhearsay labelat face value.” Id., at 106; see id., at 132 (Kagan,J., dissenting). Instead, we conduct an independent analysis ofwhether an out-of-court statement was admitted for its truth, andtherefore may have compromised a defendant’s right ofconfrontation.We did just that in Tennessee v.Street—and in so doing showcased how an out-of-courtstatement can come into evidence for a non-truth-related reason.See 471 U.S., at 410–417. Street was charged with murder,based mostly on a stationhouse confession. At trial, he claimedthat the confession was coerced, and in a peculiar way: Thesheriff, he said, had read aloud an accomplice’s confession andforced him to repeat it. On rebuttal, the State introduced theother confession (through the sheriff’s testimony) todemonstrate to the jury all the ways its content deviated fromStreet’s. We upheld that use as “nonhearsay.” Id., at 413.The other confession came in, we explained, not to prove “the truthof [the accomplice’s] assertions” about how the murder happened,but only to disprove Street’s claim about how the sheriff elicitedhis own confession. Ibid. Or otherwise said, the point wasto show, by highlighting the two confessions’ differences, thatStreet’s was not a “coerced imitation.” Id., at 414. Forthat purpose, the truth of the accomplice’s confession (and thecredibility of the accomplice himself) was irrelevant.But truth is everything when it comes to thekind of basis testimony presented here. If an expert for theprosecution conveys an out-of-court statement in support of hisopinion, and the statement supports that opinion only if true, thenthe statement has been offered for the truth of what it asserts.How could it be otherwise? “The whole point” of the prosecutor’seliciting such a statement is “to establish—because of the[statement’s] truth—a basis for the jury to credit thetestifying expert’s” opinion. Stuart, 586 U.S., at ___(Gorsuch, J., dissenting from denial of certiorari) (slip op., at3) (emphasis in original). Or said a bit differently, the truth ofthe basis testimony is what makes it useful to the prosecutor; thatis what supplies the predicate for—and thus gives value to—thestate expert’s opinion. So “[t]here is no meaningful distinctionbetween disclosing an out-of-court statement” to “explain the basisof an expert’s opinion” and “disclosing that statement for itstruth.” Williams, 567 U.S., at 106 (Thomas, J.,concurring in judgment). A State may use only the former label, butin all respects the two purposes merge.Or to see the point another way, consider itfrom the factfinder’s perspective. In the view of the Arizonacourts, an expert’s conveyance of another analyst’s report enablesthe factfinder to “determine whether [the expert’s] opinion shouldbe found credible.” Karp, 236 Ariz., at 124, 336 P.3d,at 757; see Williams, 238 Ill. 2d, at 144, 939 N.E.2d, at 278 (also stating that such a report “aid[s] the jury inassessing the value of [the expert’s] opinion”); supra, at6, 10. That is no doubt right. The jury cannot decide whether theexpert’s opinion is credible without evaluating the truth of thefactual assertions on which it is based. See D. Kaye, D. Bernstein,A. Ferguson, M. Wittlin, & J. Mnookin, The New Wigmore: ExpertEvidence §5.4.1, p. 271 (3d ed. 2021). If believed true, that basisevidence will lead the jury to credit the opinion; if believedfalse, it will do the opposite. See Williams, 567U.S., at 106, and n.1 (Thomas, J., concurring injudgment); id., at 126–127 (Kagan, J., dissenting). But thatvery fact is what raises the Confrontation Clause problem. For thedefendant has no opportunity to challenge the veracity of theout-of-court assertions that are doing much of the work.And if that explanation seems a bit abstract,then take this case as its almost-too-perfect illustration. Recallthat Rast tested eight seized items before she disappeared from thescene. At trial, the prosecutor asked the State’s “substituteexpert” Longoni to testify about four of them (with the restdropping out of the case). App. to Pet. for Cert. 26a. A recap oftheir exchange about one item will be enough; the rest followed thesame pattern. Remember as you read that Longoni, though familiarwith the lab’s general practices, had no personal knowledge aboutRast’s testing of the seized items. Rather, as his testimony makesclear, what he knew on that score came only from reviewing Rast’srecords. With that as background:Q Turn your attention to Item 26. I’m going tohand you what’s been marked as State’s Exhibit 98 [Rast’snotes].... Did you review how [Item] 26 wastested in this case?A Yes.Q When you reviewed it, did you notice whetherthe [standard lab] policies and practices that you have justdescribed were followed?A Yes.Q Were they followed?A Yes..     .     .     .     .Q From your review of the lab notes in thiscase, can you tell me what scientific method was used to analyzeItem 26?A Yes.Q And what was used?A The microscopic examination and the chemicalcolor test....Q That was done in this case?A Yes, it was.Q Was there a blank done to preventcontamination, make sure everything was clean?A According to the notes, yes..     .     .     .     .Q In reviewing what was done, your knowledgeand training as a forensic scientist, your knowledge and experiencewith DPS’s policies, practices, procedures, your knowledge ofchemistry, the lab notes, the intake records, the chemicals used,the tests done, can you form an independent opinion on the identityof Item 26?A Yes.Q What is that opinion?A That is a usable quantity of marijuana.Id., at 39a–42a, 46a. And then theprosecutor went on to Items 20A, 20B, and 28, asking similarquestions, receiving similar answers based on Rast’s records, andfinally eliciting similar “independent opinions”—which were no morethan what Rast herself had concluded. See supra, at 8–9.“Yes,” Longoni confirmed, just as Item 26 was a “usable quantity ofmarijuana,” Items 20A and 20B were “usable quantit[ies] ofmethamphetamine” and Item 28 was a “usable quantity of cannabis.”App. to Pet. for Cert. 46a, 47a, 49a.Rast’s statements thus came in for their truth,and no less because they were admitted to show the basis ofLongoni’s expert opinions. All those opinions were predicated onthe truth of Rast’s factual statements. Longoni could opine thatthe tested substances were marijuana, methamphetamine, and cannabisonly because he accepted the truth of what Rast had reported abouther work in the lab—that she had performed certain tests accordingto certain protocols and gotten certain results. And likewise, thejury could credit Longoni’s opinions identifying the substancesonly because it too accepted the truth of what Rast reported abouther lab work (as conveyed by Longoni). If Rast had lied about allthose matters, Longoni’s expert opinion would have counted fornothing, and the jury would have been in no position to convict. Sothe State’s basis evidence—more precisely, the truth of thestatements on which its expert relied—propped up its whole case.But the maker of those statements was not in the courtroom, andSmith could not ask her any questions.Approving that practice would make our decisionsin Melendez-Diaz and Bullcoming a dead letter, andallow for easy evasion of the Confrontation Clause. As earlierdescribed, those two decisions applied Crawford in“straightforward” fashion to forensic evidence.Melendez-Diaz, 557 U.S., at 312; seeBullcoming, 564 U.S., at 659–661; supra, at3–5. The first prevented the introduction of a lab analyst’stestimonial report sans lab analyst. The second refused to accedeto the idea that any old analyst—i.e., a substitute who hadnot taken part in the lab work—would do. Arizona offers only aslight variation. On its view, a surrogate analyst can testify toall the same substance—that is, someone else’s substance—as long ashe bases an “independent opinion” on that material. And that istrue even if, as here, the proffered opinion merely replicates,rather than somehow builds on, the testing analyst’s conclusions.So every testimonial lab report could come into evidence throughany trained surrogate, however remote from the case. And nodefendant would have a right to cross-examine the testing analystabout what she did and how she did it and whether her resultsshould be trusted. In short, Arizona wants to end run all we haveheld the Confrontation Clause to require. It cannot.Properly understood, the Clause still allowsforensic experts like Longoni to play a useful role in criminaltrials. Because Longoni worked in the same lab as Rast, he couldtestify from personal knowledge about how that lab typicallyfunctioned—the standards, practices, and procedures it used to testseized substances, as well as the way it maintained chains ofcustody. (Indeed, Longoni did just that in a different part of histestimony. See App. to Pet. for Cert. 32a–39a.) Or had he not beenfamiliar with Rast’s lab, he could have testified in general termsabout forensic guidelines and techniques—perhaps explaining what itmeans for a lab to be accredited and what requirementsaccreditation imposes. Or as the Williams plurality anddissent both observed, he might have been asked—and could haveanswered—any number of hypothetical questions, taking the form of:“If or assuming some out-of-court statement weretrue, what would follow from it?” See 567 U.S., at 67–68;id., at 129, n.2. (The State of course would then haveto separately prove the thing assumed.) The United States,appearing as amicus curiae in support of neither party,usefully addressed these matters at oral argument, distinguishingLongoni’s testimony as block-quoted above from the various kinds oftestimony just described. See Tr. of Oral Arg. 36–41. The latterforms of testimony allow forensic expertise to inform a criminalcase without violating the defendant’s right of confrontation. Andwe offer these merely as examples; there may be others.But as the United States acknowledged, the bulkof Longoni’s testimony took no such permissible form. Ibid.Here, the State used Longoni to relay what Rast wrote down abouthow she identified the seized substances. Longoni thus effectivelybecame Rast’s mouthpiece. He testified to the precautions (shesaid) she took, the standards (she said) she followed, the tests(she said) she performed, and the results (she said) she obtained.The State offered up that evidence so the jury would believe it—inother words, for its truth. So if the out-of-court statements werealso testimonial, their admission violated the ConfrontationClause. Smith would then have had a right to confront the personwho actually did the lab work, not a surrogate merely reading fromher records.IIIWhat remains is whether the out-of-courtstatements Longoni conveyed were testimonial. As earlier explained,that question is independent of everything said above: To implicatethe Confrontation Clause, a statement must be hearsay (“for thetruth”) and it must be testimonial—and those two issues areseparate from each other. See supra, at 3. The latter, thisCourt has stated, focuses on the “primary purpose” of thestatement, and in particular on how it relates to a future criminalproceeding. See ibid. (noting varied formulations of thestandard).[5] A court musttherefore identify the out-of-court statement introduced, and mustdetermine, given all the “relevant circ*mstances,” the principalreason it was made. Bryant, 562 U.S., at 369.But that issue is not now fit for ourresolution. The question presented in Smith’s petition forcertiorari did not ask whether Rast’s out-of-court statements weretestimonial. See supra, at 11, n.3 (quoting Pet. forCert. i). Instead, it took as a given that they were. Seeid., at i. That presentation reflected the Arizona Court ofAppeals’ opinion. As described earlier, that court relied on the“not for the truth” rationale we have just rejected. Seesupra, at 10. It did not decide whether Rast’s statementswere testimonial. Nor, to our knowledge, did the trial court evertake a stance on that issue. Because “we are a court of review, notof first view,” we will not be the pioneer court to decide thematter. Cutter v. Wilkinson, 544U.S. 709, 718, n.7 (2005). And indeed, we are not sure ifthere remains a matter to decide. Smith argues that the State hasforfeited the argument: Arizona, he says, “gave no hint in theproceedings below that it believed Rast’s statements were anythingbut testimonial.” Reply Brief 3. The State denies that assertion,pointing to a passage about Williams in its lower courtbriefing. See Brief for Arizona 39, n.14. The dispute is bestaddressed by a state court. So we return the testimonial issue,including the threshold forfeiture matter, to the Arizona Court ofAppeals.But we offer a few thoughts, based on thearguments made here, about the questions the state court mightusefully address if the testimonial issue remains live. First, thecourt will need to consider exactly which of Rast’s statements areat issue. In this Court, the parties disputed whether Longoni wasreciting from Rast’s notes alone, or from both her notes and finalreport. See supra, at 8–9 (describing those documents). InArizona’s view, everything Longoni testified to came from Rast’snotes; although he at times used the word “report,” a closecomparison of the documents and his testimony reveals (the Statesays) that he meant only the notes. See Brief for Arizona 39–40;Tr. of Oral Arg. 69–72; see also App. to Pet. for Cert. 39a–40a,48a. Smith disagrees, taking Longoni’s references to the “report,”as well as the notes, at face value. According to Smith, Longoni“relied on both” documents and in fact “treated them as a unit,”with the notes “attached” to the report as “essentially anappendix.” Reply Brief 4; Tr. of Oral Arg. 25, 98. Resolving thatdispute might, or then again might not, affect the court’s ultimatedisposition of Smith’s Confrontation Clause claim. We note onlythat before the court can decide the primary purpose of theout-of-court statements introduced at Smith’s trial, it needs todetermine exactly what those statements were.In then addressing the statements’ primarypurpose—why Rast created the report or notes—the court shouldconsider the range of recordkeeping activities that lab analystsengage in. See generally supra, at 3 (describingformulations of the testimonial inquiry). After all, some recordsof lab analysts will not have an evidentiary purpose. The UnitedStates as amicus curiae notes, for example, that lab recordsmay come into being primarily to comply with laboratoryaccreditation requirements or to facilitate internal review andquality control. See Tr. of Oral Arg. 51. Or some analysts’ notesmay be written simply as reminders to self. See id., at 20,52. In those cases, the record would not count as testimonial. Todo so, the document’s primary purpose must have “a focus on court.”Id., at 52. And again, the state court on remand should makethat assessment as to each record whose substance Longoniconveyed.IVOur holding today follows from all this Courthas held about the Confrontation Clause’s application to forensicevidence. A State may not introduce the testimonial out-of-courtstatements of a forensic analyst at trial, unless she isunavailable and the defendant has had a prior chance tocross-examine her. See Crawford, 541 U.S., at 68;Melendez-Diaz, 557 U.S., at 311. Neither may the Stateintroduce those statements through a surrogate analyst who did notparticipate in their creation. See Bullcoming, 564U.S., at 663. And nothing changes if the surrogate—as in thiscase—presents the out-of-court statements as the basis for hisexpert opinion. Those statements, as we have explained, come intoevidence for their truth—because only if true can they provide areason to credit the substitute expert. So a defendant has theright to cross-examine the person who made them.That means Arizona does not escape theConfrontation Clause just because Rast’s records came in to explainthe basis of Longoni’s opinion. The Arizona Court of Appealsthought otherwise, and so we vacate its judgment. To address theadditional issue of whether Rast’s records were testimonial(including whether that issue was forfeited), we remand the casefor further proceedings not inconsistent with this opinion.It is so ordered.

SUPREME COURT OF THE UNITED STATES_________________No. 22–899_________________JASON SMITH, PETITIONER v. ARIZONAon writ of certiorari to the court of appealsof arizona, division one[June 21, 2024]Justice Thomas, concurring in part.I join the Court in all but Part III of itsopinion. The Sixth Amendment’s Confrontation Clause provides: “Inall criminal prosecutions, the accused shall enjoy the right... to be confronted with the witnesses against him.”This Clause bars the admission of an absent witness’s testimonialstatements for their truth, unless the witness is unavailable andthe defendant previously had an opportunity to cross-examine thatwitness. See Crawford v. Washington, 541 U.S.36, 50–56, 60, n.9 (2004). Today, the Court correctlyconcludes that “[w]hen an expert conveys an absent analyst’sstatements in support of his opinion, and the statements providethat support only if true, then the statements come into evidencefor their truth.” Ante, at 2; see also Williams v.Illinois, 567 U.S.50, 106 (2012) (Thomas, J., concurring in judgment). But, aquestion remains whether that analyst’s statements weretestimonial. I agree with the Court that, because the courts belowdid not consider this question, we should remand for the ArizonaCourt of Appeals to answer it in the first instance. Ante,at 19–20. But, I disagree with the Court’s suggestion that theArizona Court of Appeals should answer that question by looking toeach statement’s “primary purpose.” Ante, at 20–21.I continue to adhere to my view that “theConfrontation Clause is implicated by extrajudicial statements onlyinsofar as they are contained in formalized testimonial materials,such as affidavits, depositions, prior testimony, orconfessions.”[1]*White v. Illinois, 502 U.S.346, 365 (1992) (Thomas, J., concurring in part and concurringin judgment); see also Ohio v. Clark, 576 U.S.237, 254–255 (2015) (Thomas, J., concurring in judgment);Williams, 567 U.S., at 110–111 (opinion of Thomas,J.); Michigan v. Bryant, 562U.S. 344, 379 (2011) (Thomas, J., concurring in judgment);Melendez-Diaz v. Massachusetts, 557 U.S.305, 329 (2009) (Thomas, J., concurring); Giles v.California, 554 U.S.353, 377–378 (2008) (Thomas, J., concurring); Davis v.Washington, 547 U.S.813, 837 (2006) (opinion of Thomas, J.); Lilly v.Virginia, 527 U.S.116, 143 (1999) (Thomas, J., concurring in part and concurringin judgment). The Confrontation Clause guarantees a criminaldefendant “the right ... to be confronted with thewitnesses against him.” Amdt. 6. As I have previously explained,“[w]itnesses ... are those who bear testimony. Andtestimony is a solemn declaration or affirmation made for thepurpose of establishing or proving some fact.” Davis, 547U.S., at 836 (opinion of Thomas, J.) (citation, internalquotation marks, and alterations omitted). This understanding isgrounded in “[t]he history surrounding the right to confrontation,”which “was developed to target particular practices that occurredunder the English bail and committal statutes passed during thereign of Queen Mary, namely, the civil-law mode of criminalprocedure, and particularly its use of exparteexaminations as evidence against the accused.” Id., at 835(internal quotation marks omitted). Rather than attempt to divine astatement’s “primary purpose,” I would look for whether thestatement is “similar in solemnity to the Marian examinationpractices that the Confrontation Clause was designed to prevent.”Williams, 567 U.S., at 112 (opinion of Thomas, J.). Inmy view, the Arizona Court of Appeals should consider on remandwhether the statements at issue have the requisite formality andsolemnity to qualify as testimonial. If they do not, theConfrontation Clause poses no barrier to their admission.

SUPREME COURT OF THE UNITED STATES_________________No. 22–899_________________JASON SMITH, PETITIONER v. ARIZONAon writ of certiorari to the court of appealsof arizona, division one[June 21, 2024]Justice Alito, with whom the Chief Justicejoins, concurring in the judgment.Today, the Court inflicts a needless,unwarranted, and crippling wound on modern evidence law. There wasa time when expert witnesses were required to express theiropinions as responses to hypothetical questions. But eventually,this highly artificial, awkward, confusing, and abuse-laden form oftestimony earned virtually unanimous condemnation. More than acentury ago, judges, evidence scholars, and legal reformassociations began to recommend that courts abandon the requireduse of hypotheticals, and more than 50 years ago, the Federal Rulesof Evidence did so. Now, however, the Court proclaims that aprosecution expert will frequently violate the Confrontation Clausewhen he testifies in strict compliance with the Federal Rules ofEvidence and similar modern state rules. Instead, the Courtsuggests that such experts revert to the form that was buried ahalf-century ago. Ante, at 18. There is no good reason forthis radical change.ITo explain why I think the Court has gone farastray, I begin with a brief look at the history of experttestimony—and particularly, why the hypothetical-questionrequirement was replaced by the (superior) mode of testimonyallowed by the Federal Rules of Evidence.AExpert testimony presents a challenge for alegal system like ours that restricts a fact-finder’s ability toconsider hearsay. This is so because an expert’s opinion very oftenis based on facts that are not proved in court. As a moderntreatise puts it, the value of experts lies in their ability to“brin[g] to bear a body of knowledge largely extraneous to thefacts of the particular case.” D. Kaye, D. Bernstein, A. Ferguson,M. Wittlin, & J. Mnookin, The New Wigmore: Expert Evidence§1.2.1, p. 4 (3d ed. 2021) (Kaye). Wigmore made the same point whenhe wrote that “[n]o one professional man can know from personalobservation more than a minute fraction of the data which he mustevery day treat as working truths.” 1 J. Wigmore, Evidence §665(3),p. 762 (1904) (Wigmore). Instead, experts routinely “rel[y] on thereported data of fellow-scientists, learned by perusing theirreports in books and journals.” Id., at 762–763 (emphasisdeleted); see also Kaye §4.1, at 165 (“[P]art of an expert’s veryexpertise inevitably derive[s] from hearsay”).Despite this problem, courts in Great Britainand this country long ago recognized the value of expert testimonyand concluded that they “must ... accept this kind ofknowledge from scientific men,” even if it meant allowing testimonybased on facts of which the expert did not have firsthandknowledge. See 1 Wigmore 763; 1 S. Greenleaf, Evidence §430(l), p.529 (rev. 16th ed. 1899) (“It would be absurd to deny judicialstanding to such knowledge, because all scientific data must behanded down from generation to generation by hearsay, and eachstudent can hope to test only a trifling fraction of scientifictruth by personal experience”); Slocovich v. Orient Mut.Ins. Co., 108 N.Y. 56, 64, 14 N.E. 802, 805 (1888) (“An expertis qualified to give evidence as to things which he has never seen.He may base an opinion upon facts proved by other witnesses, orupon facts assumed and embraced within the case”).Recognizing this reality, a court in thelate-18th century admitted expert testimony about the seaworthinessof a ship based on a survey conducted when the expert was notpresent. Thornton v. Royal Exchange Assurance Co.,Peake 37, 38, 170 Eng. Rep. 70, 71 (N. P. 1790). Similarly, anearly-19th century decision allowed ship surveyors to testify tothe seaworthiness of a vessel they had never seen. Beckwithv. Sydebotham, 1 Camp. 116, 170 Eng. Rep. 897 (N. P. 1807).The opposing party objected that the experts did not know theunderlying facts to be true, but the court admitted their opinionsbecause the experts’ technical knowledge could assist the jury.Ibid. The fact that “the truth of the facts stated to themwas not certainly known” went to the weight of the testimony, notit* admissibility. Ibid.Throughout the 19th and into the 20th century,experts generally testified in the form of an opinion in responseto a hypothetical question. An attorney would ask an expert toassume that certain facts were true and would then query whether aparticular conclusion could conceivably follow. See 3 S. Saltzburg,M. Martin, D. Capra, & J. Berch, Federal Rules of EvidenceManual §703.02[1] (13th ed. 2023).This procedure was highly artificial because itbore little resemblance to the way in which experts actually formopinions. And the procedure surely did not conform to the way layjurors think and speak.The procedure’s aim was to prevent a jury fromjumping to the conclusion that the facts packed into thehypothetical were true, but it is questionable whether the practiceachieved that objective. For instance, here is the question thatdefense counsel asked a psychiatric witness in Charles Guiteau’strial for murdering President Garfield:“Q. ... Assume it to be a factthat there was a strong hereditary taint of insanity in the bloodof the prisoner at the bar; also that at about the age ofthirty-five years his mind was so much deranged that he was a fitsubject to be sent to an insane asylum; also that at differenttimes from that date during the next succeeding five years hemanifested such decided symptoms of insanity, without stimulation,that many different persons conversing with him and observing hisconduct believed him to be insane; also that during the month ofJune, 1881, at about the expiration of said term of five years, hehonestly became dominated by the idea that he was inspired of Godto remove by death the President of the United States; also that heacted upon what he believed to be such inspiration, and what hebelieved to be in accordance with the Divine will, in preparationfor and in the accomplishment of such purpose; also that hecommitted the act of shooting the President under what he believedto be a Divine command which he was not at liberty to disobey, andwhich belief amounted to a conviction that controlled hisconscience and over-powered his will as to that act, so that hecould not resist the mental pressure upon him; also thatimmediately after the shooting he appeared calm and as one relievedby the performance of a great duty; also that there was no otheradequate motive for the act than the conviction that he wasexecuting the Divine will for the good of his country—assuming allthese propositions to be true, state whether in your opinion theprisoner was sane or insane at the time of shooting PresidentGarfield?“A. Assuming those to be true, I should say theprisoner was insane.” C. Rosenberg, The Trial of the AssassinGuiteau 144–145 (1968) (Rosenberg).How likely is it that a jury hearing a questionlike that would keep in mind that all the facts loaded into thequestion were merely hypothetical and not necessarily supported bythe evidence in the case?The Guiteau example illustrates many otherproblems with hypothetical questioning. For one, hypotheticalquestions were “difficult for the attorneys to frame, for the courtto rule on, and for the jury to understand.” M. Ladd, ExpertTestimony, 5 Vand. L. Rev. 414, 425 (1952) (Ladd). Like thequestion above, the hypotheticals were often “so built up andcontrived” that they were impossible for either the jury or theexpert to follow. 1 J. Wigmore, Evidence 1095 (2d ed. 1923) (1Wigmore 2d); accord, Ladd 427. One case involved a hypotheticalthat extended over “eighty-three pages of typewritten transcript,and an objection involved in fourteen pages more of the record.”Treadwell v. Nickel, 194 Cal. 243, 266, 228 P. 25, 35(1924). Such questions required an expert to have the extraordinaryability “to comprehend in one mental operation the entirety of whathas been asked so as to give any answer.” Ladd 427; see,e.g., Editorials, The Hypothetical Question Again, 24 J.Crim. L. & C. 517, 517–519 (1933). And juries surely foundfollowing lengthy hypotheticals even more mystifying.For another, lawyers often used hypotheticals asa preview of their closing arguments. See, e.g.,Rosenberg 144 (“Assume ... that he committed the act ofshooting the President under what he believed to be a Divinecommand which he was not at liberty to disobey ... sothat he could not resist the mental pressure upon him”); see alsoS. Gross, Expert Evidence, 1991 Wis. L. Rev. 1113, 1162 (Gross);Wigmore 2d §686, at 1095; Ladd 246. In doing so, they sometimessneaked in “irrelevant” information, Gross 1162, and excludednecessary details, W. White, Insanity and the Criminal Law 86(1923) (White) (describing the hypothetical question as“eliminat[ing] from consideration every human element which everycommon-sense man takes into consideration when he formulates anopinion”). One medical expert declared that he “ha[d] never known ahypothetical question, in a trial involving the mental condition ofthe defendant, which in [his] opinion offered a fair presentationof the case.” Ibid. As a result, experts either providedanswers that were entirely disconnected from “the actual case,” 1Wigmore 2d §686, at 1095, or else they ignored the hypotheticalaltogether, White 87.Because opposing counsel often disagreed forstrategic reasons about which facts should be included in ahypothetical, constructing a hypothetical that the judge wouldpermit was often a tricky and contentious business. If counsel didnot include enough facts to satisfy opposing counsel, thehypothetical would be met with an objection, and its sufficiencywould provide grist for an appeal. F. Rossi, Expert Witnesses 114(1991). The threat of dragging out litigation led counsel to maketheir hypotheticals even longer and more confusing.Ibid.By the early-20th century, this form oftestimony was scorned. In the second edition of his treatise,issued in 1923, Wigmore proclaimed the hypothetical question “thatfeature which does most to disgust men of science with the law ofEvidence.” 1 Wigmore 2d §686, at 1094. Around the same time, JudgeLearned Hand labeled hypotheticals “the most horific and grotesquewen upon the fair face of justice.” Address of L. Hand: TheDeficiencies of Trials to Reach the Heart of the Matter, inLectures on Legal Topics, 1921–1922, p. 104 (1926). ProfessorCharles T. McCormick described hypotheticals as “an obstruction tothe administration of justice.” Some Observations Upon the OpinionRule and Expert Testimony, 23 Texas L. Rev. 109, 128 (1945)(McCormick). Experts shared these concerns; one lamented thatlawyers’ use of hypothetical questions was often “so unfair andconfusing and degrading that it does not clarify the issue nor helpachieve justice.” H. Hulbert, Psychiatric Testimony in ProbateProceedings, 2 Law & Contemp. Prob. 448, 455 (1935).Eventually, the use of hypothetical questions was “nearlyuniversally recognized as a practical disaster” by lawyers, judges,and witnesses alike. Kaye §4.4, at 189.This state of affairs sparked efforts toeliminate hypothetical questions as a requirement. See,e.g., 1 Wigmore 2d §686, at 1094 (“The HypotheticalQuestion must go, as a requirement. Its abuses have become soobstructive and nauseous that no remedy short of extirpation willsuffice” (emphasis deleted)). Change began first in the courts,which allowed experts to sit through trial and then provide theiropinion “‘upon the evidence.’” 3 C. Chamberlayne,Modern Law of Evidence §§2482, 2483, pp. 3343–3346 (1912).More formalized rule changes soon followed. In1937, the Commissioners on Uniform State Laws incorporated aprovision in their Model Expert Testimony Act that permittedexperts to give their opinions without preliminarily disclosingtheir underlying facts or data. Advisory Committee’s Notes to Fed.Rule Evid. 705. In quick succession, both the Model Code ofEvidence, issued by the American Law Institute in 1942, and theUniform Rules of Evidence, approved by the American Bar Associationin 1953, recommended abandonment of hypothetical questions. SeeALI, Model Code of Evidence Rule 409, Comment b, p. 211 (thehypothetical question “has been so grossly abused as to be almost ascandal”); Uniform Rules of Evidence, Rule 58, Comment, p. 194(“This rule does away with the necessity of following the practice(grossly abused) of using the hypothetical question”). In 1972, theFederal Rules of Evidence followed suit with Rules 703 and 705, andmany States made similar changes.BWhat replaced hypotheticals was the procedureexemplified by the Federal Rules of Evidence.[1] Rule 703 provides that an expert’s opinion maybe based on “facts or data in the case that the expert has beenmade aware of or personally observed.” And “[u]nless the courtorders otherwise,” Rule 705 permits the expert to “state anopinion—and give the reasons for it—without first testifying to theunderlying facts or data.”These facts or data need not be “admissible” inevidence, and they are not admitted for the truth of what theyassert. Fed. Rule Evid. 703. Instead, these facts or datamay, under some circ*mstances, be disclosed to the jury fora limited purpose: to assist the jurors in judging the weight thatshould be given to the expert’s opinion. Ibid. However, thisis not allowed unless the court determines that “their probativevalue in helping the jury evaluate the [expert’s] opinionsubstantially outweighs their prejudicial effect.” Ibid. Andto prevent the jury from improperly relying on basis testimony forthe truth of the matters it asserts, a judge must instructthe jury upon request to consider such evidence only to assess thequality of the expert’s testimony (i.e., to determinewhether an expert’s statements are reliable). See AdvisoryCommittee’s Notes on Fed. Rule Evid. 703, 28 U.S.C.App., p. 393; Fed. Rule Evid. 105 (“If the court admits evidencethat is admissible ... for a [limited] purpose—but not... for another purpose—the court, on timely request,must restrict the evidence to its proper scope and instruct thejury accordingly”).This procedure is sensitive to the risk ofjurors’ mistakenly treating an expert’s basis testimony as evidenceof the truth of the facts of data upon which the expert relied. TheRules provide important safeguards against this danger, such as thestringent “probative value versus potential prejudice” test and therequirement that a limiting instruction be given upon request.Plus, of course, an expert’s lack of personal knowledge of the“facts or data” that are called to his attention can be brought outin cross examination and stressed in a closing argument.This modern system is more honest because itreflects how experts actually form opinions. See AdvisoryCommittee’s Notes on Fed. Rule Evid. 703, at 393 (describing theRule as “designed to ... bring the judicial practice inline with the practice of the experts themselves when not incourt”). It is simpler and less likely to confuse. And it avoidsmany of the pitfalls of the old procedure. It may not beperfect—and evidence scholars have proposed a variety ofreforms—but it is unquestionably better than the old regime itreplaced.IIIn light of the woeful history of experttestimony by hypotheticals, why has the Court disinterred thatprocedural monstrosity? The Court reasons that “[i]f an expert forthe prosecution conveys an out-of-court statement in support of hisopinion, and the statement supports that opinion only if true, thenthe statement has been offered for the truth of what it asserts.”Ante, at 14. Or put differently, “the truth of the basistestimony is what makes it useful to the prosecutor; that is whatsupplies the predicate for—and thus gives value to—the stateexpert’s opinion.” Ibid. In other words, the Court seems tothink that all basis testimony is necessarily offered forits truth.This is just plain wrong. What makes basisevidence “useful” is the assistance it gives the fact-finder injudging the weight that should be given to the expert’s opinion.See Advisory Committee’s Notes on Rule 703 (basis testimony may bebrought before a jury to help it “evaluate the ...opinion”). And a trial judge must, upon request, instruct the juryto consider it only for that purpose. If a judge rules that basisevidence is not admitted for its truth and so instructs thejury, where does the Court discern a Confrontation Clauseproblem?The only possible explanation is that the Courtbelieves that juries are incapable of following such aninstruction, but that conclusion is inconsistent with commonplacetrial practice and with a whole string of our decisions. It is aroutine matter for trial judges to instruct juries that evidence isadmitted for only a limited purpose. This Court acknowledged asmuch in United States v. Abel, 469 U.S.45 (1984), when it noted that “there is no rule of evidencewhich provides that testimony admissible for one purpose andinadmissible for another purpose is thereby rendered inadmissible;quite the contrary is the case.” Id., at 56. In suchinstances, courts use limiting instructions. See Fed. Rule Evid.105; 1 R. Mosteller etal., McCormick on Evidence §59, pp.481–483 (8th ed. 2020).And this Court has repeatedly upheld thatpractice—even in “situations with potentially life-and-death stakesfor defendants” and even with respect to statements that are “someof the most compelling evidence of guilt available to a jury,”Samia v. United States, 599 U.S. 635, 646–647 (2023).These decisions “credi[t] jurors by refusing to assume that theyare either ‘too ignorant to comprehend, or were too unmindful oftheir duty to respect, instructions’ of the court.” Id., at647. Indeed, we have described the assumption “‘that jurieswill follow the instructions given them by the trial judge’”as “‘crucial’” to “the system of trial by jury.”Marshall v. Lonberger, 459 U.S.422, 438, n.6 (1983) (quoting Parker v.Randolph, 442 U.S.62, 73 (1979)); accord, Francis v. Franklin,471 U.S.307, 324–325, n.9 (1985).A brief survey of prior decisions shows howfirmly this Court has adhered to that practice. In Harris v.New York, 401 U.S.222 (1971), the Court held that statements obtained from adefendant in violation of Miranda v. Arizona,384 U.S.436 (1966), could be introduced to impeach that defendant’scredibility, so long as the jury was instructed not to considerthem as evidence of his guilt. In Walder v. UnitedStates, 347 U.S.62 (1954), the Court affirmed the use of evidence obtained inviolation of the Fourth Amendment for impeachment when the trialcourt had “carefully charged the jury” that it could not beconsidered evidence of guilt. Id., at 64. In Spencerv. Texas, 385 U.S.554 (1967), the Court upheld the admission of evidence of thedefendant’s prior criminal convictions for the purpose of sentenceenhancement, provided that the jury was instructed that thisevidence could not be used in determining guilt. In Watkinsv. Sowders, 449 U.S.341 (1981), the Court presumed that a jury could properlyevaluate an eyewitness identification “under the instructions ofthe trial judge.” Id., at 347. And in Tennessee v.Street, 471 U.S.409 (1985), the Court approved the admission of an accomplice’sincriminating confession given the “pointe[d] instruct[ions] [of]the trial court ‘not to consider the truthfulness of [theconfession] in any way whatsoever.’ ” Id., at 414–415.Most recently in Samia, we held that alimiting instruction was sufficient to defeat a ConfrontationClause claim. In that homicide case, evidence showed that Samia hadtraveled with his codefendant Stillwell to the Philippines tocommit a murder for hire. Samia, 599 U.S., at 640. Thetrial court admitted Stillwell’s confession, which, as redacted,stated that he was in a van with some “other person” whenthat person shot the victim, but the court told the jury that theconfession could be considered only for the purpose of determiningwhether Stillwell himself was guilty. Id., at 642. Samiaargued that admitting the confession even with the limitinginstruction would inevitably prejudice him because “other evidenceand statements at trial enabled the jury to immediately infer thatthe ‘other person’ described in the confession was Samia himself.”Ibid. Nevertheless, we presumed that the jury was ableto follow the limiting instruction, and we therefore affirmedSamia’s murder conviction.Our cases have recognized only one situation inwhich a limiting instruction is insufficient: where a defendant isdirectly incriminated by the extrajudicial statements of anon-testifying codefendant. Bruton v. United States,391 U.S.123 (1968). We have declined to extend that exception, seeSamia, 599 U.S., at 654, and the evidence in questionin Bruton cases is worlds away from an expert’s basistestimony. If the Court thinks otherwise, it needs to explain whybasis testimony falls into the Bruton category and creates agreater risk of juror confusion than all the other situations inwhich the Court has assumed that jurors are capable of followinglimiting instructions.IIIThe Court’s assault on modern evidence law isnot only wrongheaded; it is totally unnecessary. Today’s decisionvacates the Arizona court’s judgment because the testifyingexpert’s testimony was hearsay. I agree with that bottom line, butnot because of the majority’s novel theory that basis testimony isalways hearsay. Rather, I would vacate and remand because theexpert’s testimony is hearsay under any mainstream conception,including that of the Federal Rules of Evidence.To understand why, begin with the facts. A stateforensic scientist, Elizabeth Rast, tested items seized from thedefendant and concluded that they were marijuana andmethamphetamine. Rast took notes of her tests, see App. to Pet. forCert. 88a–126a, and she signed a report confirming the results, seeid., at 85a–87a. At trial, Rast was unavailable, so theprosecution called another forensic scientist, Greggory Longoni, toprovide his expert opinion about the testing, and Longoni relied onRast’s report in doing so.Under Rules 703 and 705, Longoni could haveoffered his expert opinion that, based on the information in Rast’sreport and notes, the items she tested contained marijuana ormethamphetamine. In so answering, he would acknowledge that herelied on Rast’s report and lab notes to reach his opinion. Hecould have also disclosed the information in the report, if thecourt found that the probative value of that informationsubstantially outweighed the risk of prejudice. See Fed. Rule Evid.703. But he could not testify that any of the information in thereport was correct—for instance, that Rast actually performed thetests she recorded or that she did so correctly. Nor could hetestify that the items she tested were the ones seized from Smith.Longoni did not have personal knowledge of any of these facts, andit is unclear what “reliable” scientific “methods” could lead himto intuit their truth from Rast’s records. Fed. Rule Evid. 702(c)(defining a permissible expert opinion).The strictures of the Federal Rules here trackthe requirements of our Confrontation Clause precedents. If Longonitestified to the truth of the fact that Rast actually performed thetests indicated in her report and notes and that she carried outthose tests properly, he violated the ConfrontationClause—assuming, of course, that the notes were “testimonial,” aquestion that the Court does not reach. But he would also violatethe Federal Rules, which do not allow experts to testify to thetruth of inadmissible hearsay. In other words, except for thequestion whether Rast’s report was “testimonial,” the Federal Rulesand the requirements of the Confrontation Clause are the same. Thiscase thus offers no occasion to blow up the Federal Rules.As it happens, I agree with the Court thatLongoni stepped over the line and at times testified to the truthof the matter asserted. The prosecution asked Longoni on severaloccasions to describe the tests that Rast performed or to swear totheir accuracy, and Longoni played along. He stated as fact thatRast followed the lab’s “typical intake process” and that shecomplied with the “policies and practices” of the lab. App. to Pet.for Cert. 40a–42a. He also testified that Rast used certain“scientific method[s]” to analyze the samples, such as performingcertain tests or running a “blank.” Id., at 41a–42a,46a–48a. By asserting these facts as true, Longoni effectivelyentered inadmissible hearsay into the record, thus implicating theConfrontation Clause. The Court could have said that—and stoppedthere.*  *  *For more than a half-century, the Federal Rulesof Evidence and similar state rules have reasonably allowed expertsto disclose the information underlying their opinion. Because theCourt places this form of testimony in constitutional doubt in manycases, I concur only in the judgment.