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SUPREME COURT OF THE UNITED STATES
_________________
No. 10–8505
_________________
SANDY WILLIAMS, PETITIONER v. ILLINOIS
on writ of certiorari to the supreme court of
illinois
[June 18, 2012]
Justice Alito announced the judgment of the
Court and delivered an opinion, in which The Chief Justice, Justice
Kennedy, and Justice Breyer join.
In this case, we decide whether Crawford v.
Washington,
541 U.S.
36, 50 (2004) , precludes an expert witness from testifying in
a manner that has long been allowed under the law of evidence.
Specifically, does Crawford bar an expert from expressing an
opinion based on facts about a case that have been made known to
the expert but about which the expert is not competent to testify?
We also decide whether Crawford substantially impedes the ability
of prosecutors to introduce DNA evidence and thus may effectively
relegate the prosecution in some cases to reliance on older, less
reliable forms of proof.
In petitioner’s bench trial for rape, the
prosecution called an expert who testified that a DNA profile
produced by an outside laboratory, Cellmark, matched a profile
produced by the state police lab using a sample of
petitioner’s blood. On direct examination, the expert
testified that Cellmark was an accredited laboratory and that
Cellmark provided the police with a DNA profile. The expert also
explained the notations on documents admitted as business records,
stating that, according to the records, vaginal swabs taken from
the victim were sent to and received back from Cellmark. The expert
made no other statement that was offered for the purpose of
identifying the sample of biological material used in deriving the
profile or for the purpose of establishing how Cellmark handled or
tested the sample. Nor did the expert vouch for the accuracy of the
profile that Cellmark produced. Nevertheless, petitioner contends
that the expert’s testimony violated the Confrontation Clause
as interpreted in Crawford.
Petitioner’s main argument is that the
expert went astray when she referred to the DNA profile provided by
Cellmark as having been produced from semen found on the
victim’s vaginal swabs. But both the Illinois Appellate Court
and the Illinois Supreme Court found that this statement was not
admitted for the truth of the matter asserted, and it is settled
that the Confrontation Clause does not bar the admission of such
statements. See id., at 59–60, n. 9 (citing Tennessee v.
Street,
471
U.S. 409 (1985) ). For more than 200 years, the law of evidence
has permitted the sort of testimony that was given by the ex- pert
in this case. Under settled evidence law, an expert may express an
opinion that is based on facts that the expert assumes, but does
not know, to be true. It is then up to the party who calls the
expert to introduce other evidence establishing the facts assumed
by the expert. While it was once the practice for an expert who
based an opinion on assumed facts to testify in the form of an an-
swer to a hypothetical question, modern practice does not demand
this formality and, in appropriate cases, permits an expert to
explain the facts on which his or her opinion is based without
testifying to the truth of those facts. See Fed. Rule Evid. 703.
That is precisely what occurred in this case, and we should not
lightly “swee[p] away an accepted rule governing the
admission of scientific evidence.” Melendez-Diaz v.
Massachusetts,
557
U.S. 305, 330 (2009) (Kennedy, J., dissenting).
We now conclude that this form of expert
testimony does not violate the Confrontation Clause because that
provision has no application to out-of-court statements that are
not offered to prove the truth of the matter asserted. When an
expert testifies for the prosecution in a criminal case, the
defendant has the opportunity to cross-examine the expert about any
statements that are offered for their truth. Out-of-court
statements that are related by the expert solely for the purpose of
explaining the assumptions on which that opinion rests are not
offered for their truth and thus fall outside the scope of the
Confrontation Clause. Applying this rule to the present case, we
conclude that the expert’s testimony did not violate the
Sixth Amendment.
As a second, independent basis for our decision,
we also conclude that even if the report produced by Cellmark had
been admitted into evidence, there would have been no Confrontation
Clause violation. The Cellmark report is very different from the
sort of extrajudicial statements, such as affidavits, depositions,
prior testimony, and confessions, that the Confrontation Clause was
originally understood to reach. The report was produced before any
suspect was identified. The report was sought not for the purpose
of obtaining evidence to be used against petitioner, who was not
even under suspicion at the time, but for the purpose of finding a
rapist who was on the loose. And the profile that Cellmark provided
was not inherently inculpatory. On the contrary, a DNA profile is
evidence that tends to exculpate all but one of the more than 7
billion people in the world today. The use of DNA evidence to
exonerate persons who have been wrongfully accused or convicted is
well known. If DNA profiles could not be introduced without calling
the technicians who participated in the preparation of the profile,
economic pressures would encourage prosecutors to forgo DNA testing
and rely instead on older forms of evidence, such as eyewitness
identification, that are less reliable. See Perry v. New Hampshire,
565 U. S. ___ (2012). The Confrontation Clause does not
mandate such an undesirable development. This conclusion will not
prejudice any defendant who really wishes to probe the reliability
of the DNA testing done in a particular case because those who
participated in the testing may always be subpoenaed by the defense
and questioned at trial.
I
A
On February 10, 2000, in Chicago, Illinois, a
young woman, L. J., was abducted while she was walking home
from work. The perpetrator forced her into his car and raped her,
then robbed her of her money and other personal items and pushed
her out into the street. L. J. ran home and reported the
attack to her mother, who called the police. An ambulance took
L. J. to the hospital, where doctors treated her wounds and
took a blood sample and vaginal swabs for a sexual-assault kit. A
Chicago Police detective collected the kit, labeled it with an
inventory number, and sent it under seal to the Illinois State
Police (ISP) lab.
At the ISP lab, a forensic scientist received
the sealed kit. He conducted a chemical test that confirmed the
presence of semen on the vaginal swabs, and he then resealed the
kit and placed it in a secure evidence freezer.
During the period in question, the ISP lab often
sent biological samples to Cellmark Diagnostics Laboratory in
Germantown, Maryland, for DNA testing. There was evidence that the
ISP lab sent L. J.’s vaginal swabs to Cellmark for
testing and that Cellmark sent back a report containing a male DNA
profile produced from semen taken from those swabs. At this time,
petitioner was not under suspicion for L. J.’s rape.
Sandra Lambatos, a forensic specialist at the
ISP lab, conducted a computer search to see if the Cellmark profile
matched any of the entries in the state DNA database. The computer
showed a match to a profile produced by the lab from a sample of
petitioner’s blood that had been taken after he was arrested
on unrelated charges on August 3, 2000.
On April 17, 2001, the police conducted a lineup
at which L. J. identified petitioner as her assailant.
Petitioner was then indicted for aggravated criminal sexual
assault, aggravated kidnaping, and aggravated robbery. In lieu of a
jury trial, petitioner chose to be tried before a state judge.
B
Petitioner’s bench trial began in April
2006. In open court, L. J. again identified petitioner as her
attacker. The State also offered three expert forensic witnesses to
link petitioner to the crime through his DNA. First, Brian Hapack,
an ISP forensic scientist, testified that he had confirmed the
presence of semen on the vaginal swabs taken from L. J. by
performing an acid phosphatase test. After performing this test, he
testified, he resealed the evidence and left it in a secure freezer
at the ISP lab.
Second, Karen Abbinanti, a state forensic
analyst, testified that she had used Polymerase Chain Reaction
(PCR) and Short Tandem Repeat (STR) techniques to develop a DNA
profile from a blood sample that had been drawn from petitioner
after he was arrested in August 2000. She also stated that she had
entered petitioner’s DNA profile into the state forensic
database.
Third, the State offered Sandra Lambatos as an
expert witness in forensic biology and forensic DNA analysis. On
direct examination, Lambatos testified about the general process of
using the PCR and STR techniques to generate DNA profiles from
forensic samples such as blood and semen. She then described how
these DNA profiles could be matched to an individual based on the
individual’s unique genetic code. In making a comparison
between two DNA profiles, Lambatos stated, it is a “commonly
accepted” practice within the scientific community for
“one DNA expert to rely on the records of another DNA
expert.” App. 51. Lambatos also testified that Cellmark was
an “accredited crime lab” and that, in her experience,
the ISP lab routinely sent evidence samples via Federal Express to
Cellmark for DNA testing in order to expedite the testing process
and to “reduce [the lab’s] backlog.” Id., at
49–50. To keep track of evidence samples and preserve the
chain of custody, Lambatos stated, she and other analysts relied on
sealed shipping containers and labeled shipping manifests, and she
added that experts in her field regularly relied on such protocols.
Id., at 50–51.
Lambatos was shown shipping manifests that were
admitted into evidence as business records, and she explained what
they indicated, namely, that the ISP lab had sent
L. J.’s vaginal swabs to Cellmark, and that Cellmark had
sent them back, along with a deduced male DNA profile. Id., at
52–55. The prosecutor asked Lambatos whether there was
“a computer match” between “the male DNA profile
found in semen from the vaginal swabs of [L. J.]” and
“[the] male DNA profile that had been identified” from
petitioner’s blood sample. Id., at 55.
The defense attorney objected to this question
for “lack of foundation,” arguing that the prosecution
had offered “no evidence with regard to any testing
that’s been done to generate a DNA profile by another lab to
be testified to by this witness.” Ibid.
The prosecutor responded: “I‘m not
getting at what another lab did.” Id., at 56. Rather, she
said, she was simply asking Lambatos about “her own testing
based on [DNA] information” that she had received from
Cellmark. Ibid. The trial judge agreed, noting, “If she says
she didn’t do her own testing and she relied on a test of
another lab and she’s testifying to that, we will see what
she’s going to say.” Ibid.
The prosecutor then proceeded, asking Lambatos,
“Did you compare the semen that had been identified by Brian
Hapack from the vaginal swabs of [L. J.] to the male DNA
profile that had been identified by Karen [Abbinanti] from the
blood of [petitioner]?” Ibid.
Lambatos answered “Yes.” Ibid.
Defense counsel lodged an objection “to the form of the
question,” but the trial judge overruled it. Ibid. Lambatos
then testified that, based on her own comparison of the two DNA
profiles, she “concluded that [petitioner] cannot be excluded
as a possible source of the semen identified in the vaginal
swabs,” and that the probability of the profile’s
appearing in the general population was “1 in 8.7 quadrillion
black, 1 in 390 quadrillion white, or 1 in 109 quadrillion Hispanic
unrelated individuals.” Id., at 57. Asked whether she would
“call this a match to [petitioner],” Lambatos answered
yes, again over defense counsel’s objection. Id., at 58.
The Cellmark report itself was neither admitted
into evidence nor shown to the factfinder. Lambatos did not quote
or read from the report; nor did she identify it as the source of
any of the opinions she expressed.
On cross-examination, Lambatos confirmed that
she did not conduct or observe any of the testing on the vaginal
swabs, and that her testimony relied on the DNA profile produced by
Cellmark. Id., at 59. She stated that she trusted Cellmark to do
reliable work because it was an accredited lab, but she admitted
she had not seen any of the calibrations or work that Cellmark had
done in deducing a male DNA profile from the vaginal swabs. Id., at
59–62.
Asked whether the DNA sample might have been
degraded before Cellmark analyzed it, Lambatos answered that, while
degradation was technically possible, she strongly doubted it had
occurred in this case. She gave two reasons. First, the ISP lab
likely would have noticed the degradation before sending the
evidence off to Cell- mark. Second, and more important, Lambatos
also noted that the data making up the DNA profile would ex- hibit
certain telltale signs if it had been deduced from a degraded
sample: The visual representation of the DNA sequence would exhibit
“specific patterns” of degradation, and she
“didn’t see any evidence” of that from looking at
the profile that Cellmark produced. Id., at 81–82.
When Lambatos finished testifying, the defense
moved to exclude her testimony “with regards to testing done
by [Cellmark]” based on the Confrontation Clause. Id., at 90.
Defense counsel argued that there was “no evidence with
regards to . . . any work done by [Cellmark] to justify
testimony coming into this case with regard to their
analysis.” Ibid. Thus, while defense counsel objected to and
sought the exclusion of Lambatos’ testimony insofar as it
implicated events at the Cellmark lab, defense counsel did not
object to or move for the exclusion of any other portion of
Lambatos’ testimony, including statements regarding the
contents of the shipment sent to or received back from Cellmark.
See id., at 55, 56, 90. See also 385 Ill. App. 3d 359,
367–368, 895 N.E.2d 961, 968 (2008) (chain-of-custody
argument based on shipping manifests waived).
The prosecution responded that
petitioner’s Confrontation Clause rights were satisfied
because he had the opportunity to cross-examine the expert who had
testified that there was a match between the DNA profiles produced
by Cellmark and Abbinanti. App. 91. Invoking Illinois Rule of
Evidence 703, [
1 ] the
prosecutor argued that an expert is allowed to disclose the facts
on which the expert’s opinion is based even if the expert is
not competent to testify to those underlying facts. She further
argued that any deficiency in the foundation for the expert’s
opinion “[d]oesn’t go to the admissibility of [that]
testi- mony,” but instead “goes to the weight of the
testimony.” App. 91.
The trial judge agreed with the prosecution and
stated that “the issue is . . . what weight do
you give the test, not do you exclude it.” Id., at 94.
Accordingly, the judge stated that he would not exclude
Lambatos’ testimony, which was “based on her own
independent testing of the data received from [Cellmark].”
Id., at 94–95 (alteration in original).
The trial court found petitioner guilty of the
charges against him. The state court of appeals affirmed in
relevant part, concluding that Lambatos’ testimony did not
violate petitioner’s confrontation rights because the Cell-
mark report was not offered into evidence to prove the truth of the
matter it asserted. See 385 Ill. App. 3d, at 369, 895
N. E. 2d, at 969–970 (“Cellmark’s
report was not offered for the truth of the matter asserted;
rather, it was offered to provide a basis for Lambatos’
opinion”) The Supreme Court of Illinois also affirmed. 238
Ill. 2d 125, 939 N.E.2d 268 (2010). Under state law, the court
noted, the Cellmark report could not be used as substantive
evidence. When Lambatos referenced the report during her direct
examination, she did so “for the limited purpose of
explaining the basis for [her expert opinion],” not for the
purpose of showing “the truth of the matter asserted”
by the report. Id., at 150, 939 N. E. 2d, at 282. Thus, the
report was not used to establish its truth, but only “to show
the underlying facts and data Lambatos used before rendering an
expert opinion.” Id., at 145, 939 N. E. 2d, at 279.
We granted certiorari. 564 U. S. ___
(2011).
II
A
The Confrontation Clause of the Sixth
Amendment provides that, “[i]n all criminal prosecutions, the
accused shall enjoy the right . . . to be confronted with
the wit- nesses against him.” Before Crawford, this Court
took the view that the Confrontation Clause did not bar the
admission of an out-of-court statement that fell within a firmly
rooted exception to the hearsay rule, see Ohio v. Roberts,
448 U.S.
56, 66 (1980) , but in Crawford, the Court adopted a
fundamentally new interpretation of the confronta- tion right,
holding that “[t]estimonial statements of witnesses absent
from trial [can be] admitted only where the declarant is
unavailable, and only where the defendant has had a prior
opportunity to cross-examine.” 541 U. S., at 59.
Crawford has resulted in a steady stream of new cases in this
Court. See Bullcoming v. New Mexico, 564 U. S. ___ (2011);
Michigan v. Bryant, 562 U. S. ___ (2011); Melendez-Diaz,
557 U.S.
305 ; Giles v. California,
554 U.S.
353 (2008) ; Indiana v. Edwards,
554 U.S.
164 (2008) ; Davis v. Washington,
547
U.S. 813 (2006) .
Two of these decisions involved scientific
reports. In Melendez-Diaz, the defendant was arrested and charged
with distributing and trafficking in cocaine. At trial, the
prosecution introduced bags of a white powdery substance that had
been found in the defendant’s possession. The trial court
also admitted into evidence three “certificates of
analysis” from the state forensic laboratory stating that the
bags had been “examined with the following results: The
substance was found to contain: Cocaine.” 557 U. S., at
308 (internal quotation marks omitted).
The Court held that the admission of these
certificates, which were executed under oath before a notary,
violated the Sixth Amendment. They were created for “the sole
purpose of providing evidence against a defendant,” id., at
323, and were “ ‘quite plainly
affidavits,’ ” id., at 330 (Thomas, J.,
concurring). The Court emphasized that the introduction of the
report to prove the nature of the substance found in the
defendant’s possession was tantamount to “live,
in-court testimony” on that critical fact and that the
certificates did “precisely what a witness does on direct
examination.” Id., at 311 (internal quotation marks omitted).
There was no doubt that the certificates were used to prove the
truth of the matter they asserted. Under state law, “the sole
purpose of the affidavits was to provide prima facie evidence of
the composition, quality, and the net weight of the analyzed
substance.” Ibid. (internal quotation marks omitted and
emphasis deleted). On these facts, the Court said, it was clear
that the certif- icates were “testimonial statements”
that could not be introduced unless their authors were subjected to
the “ ‘cru- cible of
cross-examination.’ ” Id., at 311, 317 (quoting
Crawford, supra, at 61).
In Bullcoming, we held that another scientific
report could not be used as substantive evidence against the de-
fendant unless the analyst who prepared and certified the report
was subject to confrontation. The defendant in that case had been
convicted of driving while intoxicated. At trial, the court
admitted into evidence a forensic report certifying that a sample
of the defendant’s blood had an alcohol concentration of 0.21
grams per hundred milli- liters, well above the legal limit.
Instead of calling the analyst who signed and certified the
forensic report, the prosecution called another analyst who had not
performed or observed the actual analysis, but was only familiar
with the general testing procedures of the laboratory. The Court
declined to accept this surrogate testimony, despite the fact that
the testifying analyst was a “knowledgeable representative of
the laboratory” who could “explain the lab’s
processes and the details of the report.” 564 U. S., at
___ (Kennedy, J., dissenting) (slip op., at 1). The Court stated
simply: “The accused’s right is to be confronted with
the analyst who made the certification.” Id., at ___ (slip
op., at 2).
Just as in Melendez-Diaz, the forensic report
that was “introduce[d]” in Bullcoming
“contain[ed] a testimonial certification, made in order to
prove a fact at a criminal trial.” 564 U. S., at
___–___ (slip op., at 7–8). The report was signed by
the nontestifying analyst who had authored it, stating, “I
certify that I followed the procedures set out on the reverse of
this report, and the statements in this block are correct. The
concentration of alcohol in this sample is based on the grams of
alcohol in one hundred milliliters of blood.” App. in
Bullcoming, O. T. 2010, No. 09–10876, p. 62.
Critically, the report was introduced at trial for the substantive
purpose of proving the truth of the matter asserted by its
out-of-court author—namely, that the defendant had a
blood-alcohol level of 0.21. This was the central fact in question
at the defendant’s trial, and it was dispositive of his
guilt.
In concurrence, Justice Sotomayor highlighted
the im- portance of the fact that the forensic report had been
admitted into evidence for the purpose of proving the truth of the
matter it asserted. She emphasized that “this [was] not a
case in which an expert witness was asked for his independent
opinion about underlying testimonial reports that were not
themselves admitted into evidence.” 564 U. S., at ___
(slip op., at 6) (opinion concurring in part) (citing Fed. Rule
Evid. 703). “We would face a different question,” she
observed, “if asked to determine the constitutionality of
allowing an expert witness to discuss others’ testimonial
statements if the testimonial statements were not themselves
admitted as evidence.” Id., at ___ (slip op., at 6).
We now confront that question.
B
It has long been accepted that an expert
witness may voice an opinion based on facts concerning the events
at issue in a particular case even if the expert lacks first-hand
knowledge of those facts.
At common law, courts developed two ways to deal
with this situation. An expert could rely on facts that had already
been established in the record. But because it was not always
possible to proceed in this manner, and because record evidence was
often disputed, courts developed the alternative practice of
allowing an expert to testify in the form of a “hypothetical
question.” Under this approach, the expert would be asked to
assume the truth of certain factual predicates, and was then asked
to offer an opinion based on those assumptions. See 1 K. Broun,
McCormick on Evidence §14, p. 87 (6th ed. 2006); 1
J. Wigmore, Evidence §677, p. 1084 (2d ed. 1923)
(“If the witness is skilled enough, his opinion may be
adequately obtained upon hypothetical data alone; and it is immate-
rial whether he has ever seen the person, place or thing in
question” (citation omitted)). The truth of the premises
could then be established through independent evidence, and the
factfinder would regard the expert’s testimony to be only as
credible as the premises on which it was based.
An early example of this approach comes from the
English case of Beckwith v. Sydebotham, 1 Camp. 116, 170 Eng. Rep.
897 (K. B. 1807), where a party sought to prove the
seaworthiness of a ship, the Earl of Wycombe, by calling as
witnesses “several eminent surveyors of ships who had never
seen the ‘Earl of Wycombe.’ ” Ibid. The
opposing party objected to the testimony because it relied on facts
that were not known to be true, but the judge disagreed. Because
the experts were “peculiarly ac- quainted” with
“a matter of skill or science,” the judge said, the
“jury might be assisted” by their hypothetical opinion
based on certain assumed facts. Id., at 117, 170 Eng. Rep., at 897.
The judge acknowledged the danger of the jury’s being unduly
prejudiced by wrongly assuming the truth of the hypothetical facts,
but the judge noted that the experts could be asked on
cross-examination what their opinion of the ship’s
seaworthiness would be if different hypothetical facts were
assumed. If the party that had called the experts could not
independently prove the truth of the premises they posited, then
the experts’ “opinion might not go for much; but still
it was admissible evidence.” Ibid.
There is a long tradition of the use of
hypothetical questions in American courts. In 1887, for example,
this Court indicated its approval of the following jury
instruction:
“As to the questions, you must
understand that they are not evidence; they are mere statements to
these witnesses . . . and, upon the hypothesis or
assumption of these questions the witnesses are asked to give their
[opinion]. You must readily see that the value of the answers to
these questions depends largely, if not wholly, upon the fact
whether the statements made in these questions are sustained by the
proof. If the statements in these questions are not supported by
the proof, then the answers to the questions are entitled to no
weight, because based upon false assumptions or statements of
facts.” Forsyth v. Doolittle,
120 U.S.
73 (internal quotation marks omitted).
Modern rules of evidence continue to permit
experts to express opinions based on facts about which they lack
personal knowledge, but these rules dispense with the need for
hypothetical questions. Under both the Illinois and the Federal
Rules of Evidence, an expert may base an opinion on facts that are
“made known to the expert at or before the hearing,”
but such reliance does not constitute admissible evidence of this
underlying information. Ill. Rule Evid. 703; Fed. Rule Evid. 703.
Accordingly, in jury trials, both Illinois and federal law
generally bar an expert from disclosing such inadmissible evidence.
[
2 ] In bench trials, however,
both the Illinois and the Federal Rules place no restriction on the
revelation of such information to the factfinder. When the judge
sits as the trier of fact, it is presumed that the judge will
understand the limited reason for the disclosure of the underlying
inadmissible information and will not rely on that information for
any improper purpose. As we have noted, “[i]n bench trials,
judges routinely hear inadmissible evidence that they are presumed
to ignore when making decisions.” Harris v. Rivera,
454 U.S.
339, 346 (1981) (per curiam). There is a
“well-established presumption” that “the judge
[has] adhered to basic rules of procedure,” when the judge is
acting as a factfinder. Id., at 346–347 (emphasis added). See
also Gentile v. State Bar of Nev.,
501 U.S.
1030, 1078 (1991) (Rehnquist, C. J., dissenting).
This feature of Illinois and federal law is
important because Crawford, while departing from prior
Confrontation Clause precedent in other respects, took pains to
reaffirm the proposition that the Confrontation Clause “does
not bar the use of testimonial statements for purposes other than
establishing the truth of the matter asserted.” 541
U. S., at 59–60, n. 9 (citing Tennessee v. Street,
471
U.S. 409 ). In Street, the defendant claimed that the police
had coerced him into adopting the confession of his alleged
accomplice. The prosecution sought to rebut this claim by showing
that the defendant’s confession differed significantly from
the accomplice’s. Although the accomplice’s confession
was clearly a testimonial statement, the Court held that the jurors
could hear it as long as they were instructed to consider that
confession not for its truth, but only for the “distinctive
and limited purpose” of comparing it to the defendant’s
confession, to see whether the two were identical. Id., at 417.
III
A
In order to assess petitioner’s
Confrontation Clause argument, it is helpful to inventory exactly
what Lambatos said on the stand about Cellmark. She testified to
the truth of the following matters: Cellmark was an accredited lab,
App. 49; the ISP occasionally sent forensic samples to Cellmark for
DNA testing, ibid.; according to shipping manifests admitted into
evidence, the ISP lab sent vaginal swabs taken from the victim to
Cellmark and later received those swabs back from Cellmark, id., at
52–55; and, finally, the Cellmark DNA profile matched a
profile produced by the ISP lab from a sample of petitioner’s
blood, id., at 55–56. Lambatos had personal knowledge of all
of these matters, and therefore none of this testimony in- fringed
petitioner’s confrontation right.
Lambatos did not testify to the truth of any
other matter concerning Cellmark. She made no other reference to
the Cellmark report, which was not admitted into evidence and was
not seen by the trier of fact. Nor did she testify to anything that
was done at the Cellmark lab, and she did not vouch for the quality
of Cellmark’s work.
B
The principal argument advanced to show a
Confrontation Clause violation concerns the phrase that Lambatos
used when she referred to the DNA profile that the ISP lab received
from Cellmark. This argument is developed most fully in the
dissenting opinion, and therefore we refer to the dissent’s
discussion of this issue.
In the view of the dissent, the following is the
critical portion of Lambatos’ testimony, with the particular
words that the dissent finds objectionable italicized:
“Q Was there a computer match
generated of the male DNA profile found in semen from the vaginal
swabs of [L.J.] to a male DNA profile that had been identified as
having originated from Sandy Williams?
“A Yes, there was.” Post, at 7
(opinion of Kagan, J.) (quoting App. 56; emphasis added).
According to the dissent, the italicized phrase
violated petitioner’s confrontation right because Lambatos
lacked personal knowledge that the profile produced by Cellmark was
based on the vaginal swabs taken from the victim, L. J. As the
dissent acknowledges, there would have been “nothing wrong
with Lambatos’s testifying that two DNA profiles—the
one shown in the Cellmark report and the one derived from
Williams’s blood—matched each other; that was a
straightforward application of Lambatos’s expertise.”
Post, at 12. Thus, if Lambatos’ testimony had been slightly
modified as follows, the dissent would see no problem:
“Q Was there a computer match
generated of the male DNA profile produced by Cellmark found in
semen from the vaginal swabs of [L.J.] to a male DNA profile that
had been identified as having originated from Sandy Williams?
“A Yes, there was.” [
3 ]
The defect in this argument is that under
Illinois law (like federal law) it is clear that the putatively
offending phrase in Lambatos’ testimony was not admissible
for the purpose of proving the truth of the matter
asserted—i.e., that the matching DNA profile was “found
in semen from the vaginal swabs.” Rather, that fact was a
mere premise of the prosecutor’s question, and Lambatos
simply assumed that premise to be true when she gave her answer
indicating that there was a match between the two DNA profiles.
There is no reason to think that the trier of fact took
Lambatos’ answer as substantive evidence to establish where
the DNA profiles came from.
The dissent’s argument would have force if
petitioner had elected to have a jury trial. In that event, there
would have been a danger of the jury’s taking Lambatos’
testimony as proof that the Cellmark profile was derived from the
sample obtained from the victim’s vaginal swabs. Absent an
evaluation of the risk of juror confusion and careful jury
instructions, the testimony could not have gone to the jury.
This case, however, involves a bench trial and
we must assume that the trial judge understood that the portion of
Lambatos’ testimony to which the dissent objects was not
admissible to prove the truth of the matter asserted. [
4 ] The dissent, on the other hand,
reaches the truly remarkable conclusion that the wording of
Lambatos’ testimony confused the trial judge. Were it not for
that wording, the argument goes, the judge might have found that
the prosecution failed to introduce sufficient admissible evidence
to show that the Cellmark profile was derived from the sample taken
from the victim, and the judge might have disregarded the DNA
evidence. This argument reflects a profound lack of respect for the
acumen of the trial judge. [
5
]
To begin, the dissent’s argument finds no
support in the trial record. After defense counsel objected to
Lambatos’ testimony, the prosecutor made clear that she was
asking Lambatos only about “her own testing based on [DNA]
information” that she had received from Cellmark. App. 56.
Recognizing that Lambatos’ testimony would carry weight only
if the underlying premises could be established, the judge noted
that “the issue is . . . what weight do you
give the test [performed by Lambatos], not do you exclude
it.” Id., at 94. This echoes the old statement in Beckwith
that an expert’s opinion based on disputed premises
“might not go for much; but still it [is] admissible
evidence.” 1 Camp., at 117, 170 Eng. Rep., at 897. Both the
Illinois Appellate Court and the Illinois Supreme Court viewed the
record in this way, and we see no ground for disagreement. [
6 ]
Second, it is extraordinarily unlikely that any
trial judge would be confused in the way that the dissent posits.
That Lambatos was not competent to testify to the chain of custody
of the sample taken from the victim was a point that any trial
judge or attorney would immediately understand. Lambatos, after
all, had absolutely nothing to do with the collection of the sample
from the victim, its subsequent handling or preservation by the
police in Illinois, or its shipment to and receipt by Cellmark. No
trial judge would take Lambatos’ testimony as furnishing
“the missing link” in the State’s evidence
regarding the identity of the sample that Cellmark tested. See
post, at 6 (opinion of Kagan, J.).
Third, the admissible evidence left little room
for argument that the sample tested by Cellmark came from any
source other than the victim’s vaginal swabs. [
7 ] This is so because there is simply no
plausible explanation for how Cellmark could have produced a DNA
profile that matched Williams’ if Cellmark had tested any
sample other than the one taken from the victim. If any other items
that might have contained Williams’ DNA had been sent to
Cellmark or were otherwise in Cellmark’s possession, there
would have been a chance of a mix-up or of cross-contamination. See
District Attorney’s Office for Third Judicial Dist. v.
Osborne, 557 U.S. 52, 80 (2009) (Alito, J., concurring). But there
is absolutely nothing to suggest that Cellmark had any such items.
Thus, the fact that the Cellmark profile matched Williams—the
very man whom the victim identified in a lineup and at trial as her
at- tacker—was itself striking confirmation that the sample
that Cellmark tested was the sample taken from the victim’s
vaginal swabs. For these reasons, it is fanciful to suggest that
the trial judge took Lambatos’ testimony as providing
critical chain-of-custody evidence.
C
Other than the phrase that Lambatos used in
referring to the Cellmark profile, no specific passage in the trial
record has been identified as violating the Confrontation Clause,
but it is nevertheless suggested that the State somehow introduced
“the substance of Cellmark’s report into
evidence.” Post, at 8 (Kagan, J., dissenting). The main
impetus for this argument appears to be the (erroneous) view that
unless the substance of the report was sneaked in, there would be
insufficient evidence in the record on two critical points: first,
that the Cellmark profile was based on the semen in the
victim’s vaginal swabs and, second, that Cellmark’s
procedures were reli- able. This argument is both legally
irrelevant for present purposes and factually incorrect.
As to legal relevance, the question before us is
whether petitioner’s Sixth Amendment confrontation right was
violated, not whether the State offered sufficient foundational
evidence to support the admission of Lambatos’ opinion about
the DNA match. In order to prove these underlying facts, the
prosecution relied on circumstantial evidence, and the Illinois
courts found that this evidence was sufficient to satisfy state-law
requirements regarding proof of foundational facts. See 385 Ill.
App. 3d, at 366–368, 895 N. E. 2d, at 967–968; 238 Ill.
2d, at 138, 939 N. E. 2d, at 275. We cannot review that
interpretation and application of Illinois law. Thus, even if the
record did not contain any evidence that could rationally support a
finding that Cellmark produced a scientifically reliable DNA
profile based on L. J.’s vaginal swab, that would not
establish a Confrontation Clause violation. If there were no proof
that Cellmark produced an accurate profile based on that sample,
Lambatos’ testimony regarding the match would be irrelevant,
but the Confrontation Clause, as interpreted in Crawford, does not
bar the admission of irrelevant evidence, only testimonial
statements by declarants who are not subject to cross-examination.
[
8 ]
It is not correct, however, that the trial
record lacks admissible evidence with respect to the source of the
sam- ple that Cellmark tested or the reliability of the Cell- mark
profile. As to the source of the sample, the State offered
conventional chain-of-custody evidence, namely, the testimony of
the physician who obtained the vaginal swabs, the testimony of the
police employees who handled and kept custody of that evidence
until it was sent to Cellmark, and the shipping manifests, which
provided evidence that the swabs were sent to Cellmark and then
returned to the ISP lab. In addition, as already discussed, the
match between the Cellmark profile and petitioner’s profile
was itself telling confirmation that the Cellmark profile was
deduced from the semen on the vaginal swabs.
This match also provided strong circumstantial
evidence regarding the reliability of Cellmark’s work.
Assuming (for the reasons discussed above) that the Cellmark
profile was based on the semen on the vaginal swabs, how could
shoddy or dishonest work in the Cellmark lab [
9 ] have resulted in the production of a DNA
profile that just so happened to match petitioner’s? If the
semen found on the vaginal swabs was not petitioner’s and
thus had an en- tirely different DNA profile, how could sloppy work
in the Cellmark lab have transformed that entirely different
profile into one that matched petitioner’s? And without
access to any other sample of petitioner’s DNA (and recall
that petitioner was not even under suspicion at this time), how
could a dishonest lab technician have substituted pe-
titioner’s DNA profile? Under the circumstances of this case,
it was surely permissible for the trier of fact to infer that the
odds of any of this were exceedingly low.
This analysis reveals that much of the
dissent’s argument rests on a very clear error. The dissent
argues that Lambatos’ testimony could be “true”
only if the predicate facts asserted in the Cellmark report were
true, and therefore Lambatos’ reference to the report must
have been used for the purpose of proving the truth of those facts.
See post, at 10–11. But the truth of Lambatos’
testimony, properly understood, was not dependent on the truth of
any predicate facts. Lambatos testified that two DNA profiles
matched. The correctness of this expert opinion, which the defense
was able to test on cross-examination, was not in any way dependent
on the origin of the samples from which the profiles were derived.
Of course, Lambatos’ opinion would have lacked probative
value if the prosecution had not introduced other evidence to
establish the provenance of the profiles, but that has nothing to
do with the truth of her testimony.
The dissent is similarly mistaken in its
contention that the Cellmark report “was offered for its
truth because that is all such ‘basis evidence’ can be
offered for.” Post, at 13; see also post, at 3 (Thomas, J.,
concurring in judgment) (“[S]tatements introduced to explain
the basis of an expert’s opinion are not introduced for a
plausible nonhearsay purpose”). This view is directly
contrary to the current version of Rule 703 of the Federal Rules of
Evidence, which this Court approved and sent to Congress in 2000.
Under that Rule, “basis evidence” that is not
admissible for its truth may be disclosed even in a jury trial
under appropriate circumstances. The purpose for allowing this
disclosure is that it may “assis[t] the jury to evaluate the
expert’s opinion.” Advisory Committee’s 2000
Notes on Fed. Rule Evid. 703, 28 U. S. C. App., p. 361.
The Rule 703 approach, which was controversial when adopted, [
10 ] is based on the idea
that the disclosure of basis evidence can help the factfinder
understand the expert’s thought process and determine what
weight to give to the expert’s opinion. For example, if the
factfinder were to suspect that the expert relied on factual
premises with no support in the record, or that the expert drew an
unwarranted inference from the premises on which the expert relied,
then the probativeness or credibility of the expert’s opinion
would be seriously undermined. The purpose of disclosing the facts
on which the expert relied is to allay these fears—to show
that the expert’s reasoning was not illogical, and that the
weight of the expert’s opinion does not depend on factual
premises unsupported by other evidence in the record—not to
prove the truth of the underlying facts.
Perhaps because it cannot seriously dispute the
legit- imate nonhearsay purpose of illuminating the expert’s
thought process, the dissent resorts to the last-ditch argument
that, after all, it really does not matter whether Lambatos’
statement regarding the source of the Cellmark report was admitted
for its truth. The dissent concedes that “the trial judge
might have ignored Lambatos’s statement about the Cellmark
report,” but nonetheless maintains that “the admission
of that statement violated the Confrontation Clause even if the
judge ultimately put it aside.” Post, at 15, n. 2. But
in a bench trial, it is not necessary for the judge to stop and
make a formal statement on the record regarding the limited reason
for which the testimony is admitted. If the judge does not consider
the testimony for its truth, the effect is precisely the same.
Thus, if the trial judge in this case did not rely on the statement
in question for its truth, there is simply no way around the
proviso in Crawford that the Confrontation Clause applies only to
out-of-court statements that are “use[d]” to
“establis[h] the truth of the matter asserted.” 541
U. S., at 59–60, n. 9 (citing Street,
471
U.S. 409 ).
For all these reasons, we conclude that
petitioner’s Sixth Amendment confrontation right was not
violated.
D
This conclusion is entirely consistent with
Bullcoming and Melendez-Diaz. In those cases, the forensic reports
were introduced into evidence, and there is no question that this
was done for the purpose of proving the truth of what they
asserted: in Bullcoming that the defendant’s blood alcohol
level exceeded the legal limit and in Melendez- Diaz that the
substance in question contained cocaine. Nothing comparable
happened here. In this case, the Cellmark report was not introduced
into evidence. An expert witness referred to the report not to
prove the truth of the matter asserted in the report, i.e., that
the report contained an accurate profile of the perpetrator’s
DNA, but only to establish that the report contained a DNA profile
that matched the DNA profile deduced from petitioner’s blood.
Thus, just as in Street, the report was not to be considered for
its truth but only for the “distinctive and limited
purpose” of seeing whether it matched something else. 471
U. S., at 417. The relevance of the match was then established
by independent circumstantial evidence showing that the Cellmark
report was based on a forensic sample taken from the scene of the
crime.
Our conclusion will not open the door for the
kind of abuses suggested by some of petitioner’s amici and
the dissent. See post, at 10–11; Brief for Richard D.
Friedman as Amicus Curiae 20–21. In the hypothetical
situations posited, an expert expresses an opinion based on factual
premises not supported by any admissible evidence, and may also
reveal the out-of-court statements on which the expert relied. [
11 ] There are at least four
safeguards to prevent such abuses. First, trial courts can screen
out experts who would act as mere conduits for hearsay by strictly
enforcing the requirement that experts display some genuine
“scientific, technical, or other specialized knowledge [that]
will help the trier of fact to understand the evidence or to
determine a fact in issue.” Fed. Rule Evid. 702(a). Second,
experts are generally precluded from disclosing inadmissible
evidence to a jury. See Fed. Rule Evid. 703; People v. Pasch,
152 Ill. 2d 133, 175–176,
604 N.E.2d 294, 310–311 (1992). Third, if such evidence
is disclosed, the trial judges may and, under most circumstances,
must, instruct the jury that out-of-court statements cannot be
accepted for their truth, and that an expert’s opinion is
only as good as the independent evidence that establishes its
underlying premises. See Fed. Rules Evid. 105, 703; People v.
Scott,
148 Ill. 2d 479, 527–528,
594 N.E.2d 217, 236–237 (1992). And fourth, if the
prosecution cannot muster any independent admissible evidence to
prove the foundational facts that are essential to the relevance of
the expert’s testimony, then the expert’s testimony
cannot be given any weight by the trier of fact. [
12 ]
IV
A
Even if the Cellmark report had been
introduced for its truth, we would nevertheless conclude that there
was no Confrontation Clause violation. The Confrontation Clause
refers to testimony by “witnesses against” an accused.
Both the noted evidence scholar James Henry Wigmore and Justice
Harlan interpreted the Clause in a strictly literal sense as
referring solely to persons who testify in court, but we have not
adopted this narrow view. It has been said that “[t]he
difficulty with the Wigmore-Harlan view in its purest form is its
tension with much of the apparent history surrounding the evolution
of the right of confrontation at common law.” White v.
Illinois,
502 U.S.
346, 360 (1992) (Thomas, J., concurring). “[T]he
principal evil at which the Confrontation Clause was
directed,” the Court concluded in Crawford, “was the
civil-law mode of criminal procedure, and particularly its use of
ex parte examinations as evidence against the accused.” 541
U. S., at 50. “[I]n England, pretrial examinations of
suspects and witnesses by government officials ‘were
sometimes read in court in lieu of live
testimony.’ ” Bryant, 562 U. S., at ___ (slip
op., at 6) (quoting Crawford, supra, at 43). The Court has thus
interpreted the Confrontation Clause as prohibiting modern-day
practices that are tantamount to the abuses that gave rise to the
recognition of the confrontation right. But any further expansion
would strain the constitutional text.
The abuses that the Court has identified as
prompting the adoption of the Confrontation Clause shared the
following two characteristics: (a) they involved out-of-court
statements having the primary purpose of accusing a targeted
individual of engaging in criminal conduct and (b) they involved
formalized statements such as affidavits, depositions, prior
testimony, or confessions. In all but one of the post-Crawford
cases [
13 ] in which a
Confrontation Clause violation has been found, both of these
characteristics were present. See Bullcoming, 564 U. S., at
308 (slip op., at 3–4) (certified lab report having purpose
of showing that defendant’s blood-alcohol level exceeded
legal limit); Melendez-Diaz, 557 U. S., at 308 (certified lab
report having purpose of showing that substance connected to
defendant contained cocaine); Crawford, supra, at 38 (custodial
statement made after Miranda warnings that shifted blame from
declarant to accused). [
14
] The one exception occurred in Hammon v. Indiana,
547
U.S. 813 –832 (2006), which was decided together with
Davis v. Washington, but in Hammon and every other post-Crawford
case in which the Court has found a violation of the confrontation
right, the statement at issue had the primary purpose of accusing a
targeted individual.
B
In Hammon, the one case in which an informal
statement was held to violate the Confrontation Clause, we
considered statements elicited in the course of police in-
terrogation. We held that a statement does not fall within the
ambit of the Clause when it is made “under circumstances
objectively indicating that the primary purpose of the
interrogation is to enable police assistance to meet an ongoing
emergency.” 547 U. S., at 822. In Bryant, another
police-interrogation case, we explained that a person who makes a
statement to resolve an ongoing emergency is not acting like a
trial witness because the declarant’s purpose is not to
provide a solemn declaration for use at trial, but to bring an end
to an ongoing threat. See 562 U. S., at ___, ___ (slip op., at
11, 14). We noted that “the prospect of fabrication
. . . is presumably significantly diminished” when
a statement is made under such circumstances, id., at ___ (slip
op., at 14) and that reliability is a salient characteristic of a
statement that falls outside the reach of the Confrontation Clause,
id., at ___–___ (slip op., at 14–15). We emphasized
that if a statement is not made for “the primary purpose of
creating an out-of-court substitute for trial testimony,” its
admissibility “is the concern of state and federal rules of
evidence, not the Confrontation Clause.” Id., at
___–___ (slip op., at 11–12).
In Melendez-Diaz and Bullcoming, the Court held
that the particular forensic reports at issue qualified as
testimonial statements, but the Court did not hold that all
forensic reports fall into the same category. Introduction of the
reports in those cases ran afoul of the Confrontation Clause
because they were the equivalent of affidavits made for the purpose
of proving the guilt of a particular criminal defendant at trial.
There was nothing resembling an ongoing emergency, as the suspects
in both cases had already been captured, and the tests in question
were relatively simple and can generally be performed by a single
analyst. In addition, the technicians who prepared the reports must
have realized that their contents (which reported an elevated
blood-alcohol level and the presence of an illegal drug) would be
incriminating.
C
The Cellmark report is very different. It
plainly was not prepared for the primary purpose of accusing a
targeted individual. In identifying the primary purpose of an
out-of-court statement, we apply an objective test. Bryant, 562
U. S., at ___ (slip op., at 13). We look for the primary
purpose that a reasonable person would have ascribed to the
statement, taking into account all of the surrounding
circumstances. Ibid.
Here, the primary purpose of the Cellmark
report, viewed objectively, was not to accuse petitioner or to
create evidence for use at trial. When the ISP lab sent the sample
to Cellmark, its primary purpose was to catch a dangerous rapist
who was still at large, not to obtain evidence for use against
petitioner, who was neither in custody nor under suspicion at that
time. Similarly, no one at Cellmark could have possibly known that
the profile that it produced would turn out to inculpate
petitioner—or for that matter, anyone else whose DNA profile
was in a law enforcement database. Under these circumstances, there
was no “prospect of fabrication” and no incentive to
produce anything other than a scientifi- cally sound and reliable
profile. Id., at ___ (slip op., at 14).
The situation in which the Cellmark technicians
found themselves was by no means unique. When lab technicians are
asked to work on the production of a DNA profile, they often have
no idea what the consequences of their work will be. In some cases,
a DNA profile may provide powerful incriminating evidence against a
person who is identified either before or after the profile is
completed. But in others, the primary effect of the profile is to
exonerate a suspect who has been charged or is under investigation.
The technicians who prepare a DNA profile generally have no way of
knowing whether it will turn out to be incriminating or
exonerating—or both.
It is also significant that in many labs,
numerous technicians work on each DNA profile. See Brief for New
York County District Attorney’s Office et al. as Amici
Curiae 6 (New York lab uses at least 12 technicians for each case);
People v. Johnson, 389 Ill. App. 3d 618, 627, 906 N.E.2d 70, 79
(2009) (“[A]pproximately 10 Cellmark analysts were involved
in the laboratory work in this case”). When the work of a lab
is divided up in such a way, it is likely that the sole purpose of
each technician is simply to perform his or her task in accordance
with accepted procedures.
Finally, the knowledge that defects in a DNA
profile may often be detected from the profile itself provides a
further safeguard. In this case, for example, Lambatos testified
that she would have been able to tell from the profile if the
sample used by Cellmark had been degraded prior to testing. As
noted above, moreover, there is no real chance that “sample
contamination, sample switching, mislabeling, [or] fraud”
could have led Cellmark to produce a DNA profile that falsely
matched petitioner. Post, at 21 (Kagan, J., dissenting). At the
time of the testing, petitioner had not yet been identified as a
suspect, and there is no suggestion that anyone at Cellmark had a
sample of his DNA to swap in by malice or mistake. And given the
complexity of the DNA molecule, it is inconceivable that shoddy lab
work would somehow produce a DNA profile that just so happened to
have the precise genetic makeup of petitioner, who just so happened
to be picked out of a lineup by the victim. The prospect is beyond
fanciful.
In short, the use at trial of a DNA report
prepared by a modern, accredited laboratory “bears little if
any resemblance to the historical practices that the Confrontation
Clause aimed to eliminate.” Bryant, supra, at ___ (slip op.,
at 2) (Thomas, J., concurring).
* * *
For the two independent reasons explained
above, we conclude that there was no Confrontation Clause violation
in this case. Accordingly, the judgment of the Supreme Court of
Illinois is
Affirmed.