(Slip Opinion)              OCTOBER TERM, 2008                                       1

                                       Syllabus

         NOTE: Where it is feasible, a syllabus (headnote) will be released, as is
       being done in connection with this case, at the time the opinion is issued.
       The syllabus constitutes no part of the opinion of the Court but has been
       prepared by the Reporter of Decisions for the convenience of the reader.
       See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337.


SUPREME COURT OF THE UNITED STATES

                                       Syllabus

                           RIVERA v. ILLINOIS

        CERTIORARI TO THE SUPREME COURT OF ILLINOIS

  No. 07–9995. Argued February 23, 2009—Decided March 31, 2009
During jury selection in petitioner Rivera’s state-court first-degree
 murder trial, his counsel sought to use a peremptory challenge to ex
 cuse venire member Deloris Gomez. Rivera had already exercised
 two peremptory challenges against women, one of whom was African-
 American. It is conceded that there was no basis to challenge Gomez
 for cause. She met the requirements for jury service, and Rivera does
 not contend that she was biased against him. The trial court rejected
 the peremptory challenge out of concern that it was discriminatory.
 Under Batson v. Kentucky, 476 U. S. 79, and later decisions applying
 Batson, parties are constitutionally prohibited from exercising per
 emptory challenges to exclude jurors based on race, ethnicity, or sex.
 At trial, the jury, with Gomez as its foreperson, found Rivera guilty of
 first-degree murder. The Illinois Supreme Court subsequently af
 firmed the conviction, holding that the peremptory challenge should
 have been allowed, but rejecting Rivera’s argument that the improper
 seating of Gomez was a reversible error. Observing that the Consti
 tution does not mandate peremptory challenges and that they are not
 necessary for a fair trial, the court held that the denial of Rivera’s
 peremptory challenge was not a structural error requiring automatic
 reversal. Nor, the court found, was the error harmless beyond a rea
 sonable doubt. The court added that it did not need to decide
 whether the trial court’s denial was “an error of constitutional di
 mension” in the circumstances of Rivera’s case, a comment that ap
 pears to be related to Rivera’s arguments that, even absent a free
 standing constitutional entitlement to peremptory challenges, the
 inclusion of Gomez on his jury violated the Fourteenth Amendment’s
 Due Process Clause.
Held: Provided that all jurors seated in a criminal case are qualified
 and unbiased, the Due Process Clause does not require automatic re
2                          RIVERA v. ILLINOIS

                                  Syllabus

    versal of a conviction because of the trial court’s good-faith error in
    denying the defendant’s peremptory challenge to a juror. Pp. 6–12.
       (a) Rivera maintains that due process requires reversal whenever a
    criminal defendant’s peremptory challenge is erroneously denied. He
    asserts that a trial court that fails to dismiss a lawfully challenged
    juror commits structural error because the jury becomes an illegally
    constituted tribunal, whose verdict is per se invalid; that this is true
    even if the Constitution does not mandate peremptory challenges,
    since criminal defendants have a constitutionally protected liberty in
    terest in their state-provided peremptory challenge rights; that the
    issue is not amenable to harmless-error analysis, as it is impossible
    to ascertain how a properly constituted jury would have decided his
    case; and that automatic reversal therefore must be the rule as a
    matter of federal law. Rivera’s arguments do not withstand scrutiny.
    If a defendant is tried before a qualified jury composed of individuals
    not challengeable for cause, the loss of a peremptory challenge due to
    a state court’s good-faith error is not a matter of federal constitu
    tional concern. Rather, it is a matter for the State to address under
    its own laws. There is no freestanding constitutional right to per
    emptory challenges. See, e.g., United States v. Martinez-Salazar, 528
    U.S. 304, 311. They are “a creature of statute,” Ross v. Oklahoma,
    487 U. S. 81, 89, which a State may decline to offer at all, Georgia v.
    McCollum, 505 U. S. 42, 57. Thus, the mistaken denial of a state
    provided peremptory challenge does not, without more, violate the
    Federal Constitution. See, e.g., Engle v. Isaac, 456 U. S. 107, 121, n.
    21. The Due Process Clause safeguards not the meticulous obser
    vance of state procedural prescriptions, but “the fundamental ele
    ments of fairness in a criminal trial.” Spencer v. Texas, 385 U. S.
    554, 563–564. Pp. 6–8.
       (b) The trial judge’s refusal to excuse Gomez did not deprive Rivera
    of his constitutional right to a fair trial before an impartial jury.
    Ross is instructive. There, a criminal defendant used a peremptory
    challenge to rectify an Oklahoma trial court’s erroneous denial of a
    for-cause challenge, leaving him with one fewer peremptory challenge
    to use at his discretion. Even though the trial court’s error might
    “have resulted in a jury panel different from that which would other
    wise have decided [Ross’s] case,” 487 U. S., at 87, because no member
    of the jury as finally composed was removable for cause, there was no
    violation of his Sixth Amendment right to an impartial jury or his
    Fourteenth Amendment right to due process, id., at 86–91. This
    Court reached the same conclusion with regard to a federal-court
    trial in Martinez-Salazar, 528 U. S., at 316. Rivera’s efforts to dis
    tinguish Ross and Martinez-Salazar are unavailing. First, although
    in contrast to Rivera, the Ross and Martinez-Salazar defendants did
                   Cite as: 556 U. S. ____ (2009)                     3

                              Syllabus

not challenge any of the jurors who were in fact seated, neither Go
mez nor any other member of Rivera’s jury was removable for cause.
Thus, like the Ross and Martinez-Salazar juries, Rivera’s jury was
impartial for Sixth Amendment purposes. Rivera suggests that due
process concerns persist because Gomez knew he did not want her on
the panel, but this Court rejects the notion that a juror is constitu
tionally disqualified whenever she is aware of a challenge. Second, it
is not constitutionally significant that, in contrast to Ross and Marti
nez-Salazar, the seating of Gomez over Rivera’s peremptory chal
lenge was at odds with state law. Errors of state law do not auto
matically become violations of due process. As in Ross and Martinez-
Salazar, there is no suggestion here that the trial judge repeatedly or
deliberately misapplied the law or acted in an arbitrary or irrational
manner. Rather, his conduct reflected a good-faith effort to enforce
Batson’s antidiscrimination requirements. To hold that a one-time,
good-faith misapplication of Batson violates due process would likely
discourage trial courts and prosecutors from policing a defendant’s
discriminatory use of peremptory challenges.            The Fourteenth
Amendment does not compel such a tradeoff. Pp. 8–10.
   (c) Rivera errs in insisting that, even without a constitutional vio
lation, the deprivation of a state-provided peremptory challenge re
quires reversal as a matter of federal law. He relies on a suggestion
in Swain v. Alabama, 380 U. S. 202, 219, that “[t]he denial or im
pairment of the right [to exercise peremptory challenges] is reversible
error without a showing of prejudice.” This statement was disavowed
in Martinez-Salazar, see 528 U. S., at 317, n. 4. Typically, an error is
designated as “structural,” therefore “requir[ing] automatic reversal,”
only when “the error ‘necessarily render[s] a criminal trial fundamen
tally unfair or an unreliable vehicle for determining guilt or inno
cence.’ ” Washington v. Recuenco, 548 U. S. 212, 218–219. The mis
taken denial of a state-provided peremptory challenge does not, in
the circumstances here, constitute such an error. The automatic re
versal precedents Rivera cites are inapposite. One set of cases in
volves constitutional errors concerning the qualification of the jury or
judge. See, e.g., Batson, 476 U. S., at 86, 87. A second set of cases
involves circumstances in which federal judges or tribunals lacked
statutory authority to adjudicate the controversy, resulting in a
judgment invalid as a matter of federal law. See, e.g., Nguyen v.
United States, 539 U. S. 69. Nothing in those decisions suggests that
federal law renders state-court judgments void whenever there is a
state-law defect in a tribunal’s composition. Absent a federal consti
tutional violation, States are free to decide, as a matter of state law,
that a trial court’s mistaken denial of a peremptory challenge is re
versible error per se or, as the Illinois Supreme Court implicitly held
4                         RIVERA v. ILLINOIS

                                 Syllabus

    here, that the improper seating of a competent and unbiased juror
    could rank as a harmless error under state law. Pp. 10–12.
227 Ill. 2d 1, 879 N. E. 2d 876, affirmed.

    GINSBURG, J., delivered the opinion for a unanimous Court.
                        Cite as: 556 U. S. ____ (2009)                              1

                             Opinion of the Court

     NOTICE: This opinion is subject to formal revision before publication in the
     preliminary print of the United States Reports. Readers are requested to
     notify the Reporter of Decisions, Supreme Court of the United States, Wash
     ington, D. C. 20543, of any typographical or other formal errors, in order
     that corrections may be made before the preliminary print goes to press.


SUPREME COURT OF THE UNITED STATES
                                   _________________

                                   No. 07–9995
                                   _________________


     MICHAEL RIVERA, PETITIONER v. ILLINOIS
    ON WRIT OF CERTIORARI TO THE SUPREME COURT OF

                       ILLINOIS

                                [March 31, 2009] 


  JUSTICE GINSBURG delivered the opinion of the Court.
  This case concerns the consequences of a state trial
court’s erroneous denial of a defendant’s peremptory chal
lenge to the seating of a juror in a criminal case. If all
seated jurors are qualified and unbiased, does the Due
Process Clause of the Fourteenth Amendment nonetheless
require automatic reversal of the defendant’s conviction?
  Following a jury trial in an Illinois state court, defen
dant-petitioner Michael Rivera was convicted of first
degree murder and sentenced to a prison term of 85 years.
On appeal, Rivera challenged the trial court’s rejection of
his peremptory challenge to venire member Deloris Go
mez. Gomez sat on Rivera’s jury and indeed served as the
jury’s foreperson. It is conceded that there was no basis to
challenge Gomez for cause. She met the requirements for
jury service, and Rivera does not contend that she was in
fact biased against him. The Supreme Court of Illinois
held that the peremptory challenge should have been
allowed, but further held that the error was harmless and
therefore did not warrant reversal of Rivera’s conviction.
We affirm the judgment of the Illinois Supreme Court.
  The right to exercise peremptory challenges in state
2                    RIVERA v. ILLINOIS

                     Opinion of the Court

court is determined by state law. This Court has “long
recognized” that “peremptory challenges are not of federal
constitutional dimension.” United States v. Martinez-
Salazar, 528 U. S. 304, 311 (2000). States may withhold
peremptory challenges “altogether without impairing the
constitutional guarantee of an impartial jury and a fair
trial.” Georgia v. McCollum, 505 U. S. 42, 57 (1992). Just
as state law controls the existence and exercise of peremp
tory challenges, so state law determines the consequences
of an erroneous denial of such a challenge. Accordingly,
we have no cause to disturb the Illinois Supreme Court’s
determination that, in the circumstances Rivera’s case
presents, the trial court’s error did not warrant reversal of
his conviction.
                            I
  Rivera was charged with first-degree murder in the
Circuit Court of Cook County, Illinois. The State alleged
that Rivera, who is Hispanic, shot and killed Marcus Lee,
a 16-year-old African-American, after mistaking Lee for a
member of a rival gang.
  During jury selection, Rivera’s counsel questioned pro
spective juror Deloris Gomez, a business office supervisor
at Cook County Hospital’s outpatient orthopedic clinic.
App. 32–33. Gomez stated that she sometimes interacted
with patients during the check-in process and acknowl
edged that Cook County Hospital treats many gunshot
victims. She maintained, however, that her work experi
ence would not affect her ability to be impartial. After
questioning Gomez, Rivera’s counsel sought to use a per
emptory challenge to excuse her. Id., at 33. At that point
in the jury’s selection, Rivera had already used three
peremptory challenges. Two of the three were exercised
against women; one of the two women thus eliminated was
African-American. Illinois law affords each side seven
peremptory challenges. See Ill. Sup. Ct. Rule 434(d) (West
                 Cite as: 556 U. S. ____ (2009)           3

                     Opinion of the Court

2006).
  Rather than dismissing Gomez, the trial judge called
counsel to chambers, where he expressed concern that the
defense was discriminating against Gomez. App. 34–36.
Under Batson v. Kentucky, 476 U. S. 79 (1986), and later
decisions building upon Batson, parties are constitution
ally prohibited from exercising peremptory challenges to
exclude jurors on the basis of race, ethnicity, or sex. With
out specifying the type of discrimination he suspected or
the reasons for his concern, the judge directed Rivera’s
counsel to state his reasons for excusing Gomez. Counsel
responded, first, that Gomez saw victims of violent crime
on a daily basis. Counsel next added that he was “pulled
in two different ways” because Gomez had “some kind of
Hispanic connection given her name.” App. 34. At that
point, the judge interjected that Gomez “appears to be an
African American”—the second “African American female”
the defense had struck. Id., at 34–35. Dissatisfied with
counsel’s proffered reasons, the judge denied the challenge
to Gomez, but agreed to allow counsel to question Gomez
further.
  After asking Gomez additional questions about her work
at the hospital, Rivera’s counsel renewed his challenge.
Counsel observed, outside the jury’s presence, that most of
the jurors already seated were women. Counsel said he
hoped to “get some impact from possibly other men in the
case.” Id., at 39. The court reaffirmed its earlier ruling,
and Gomez was seated on the jury.
  Rivera’s case proceeded to trial. The jury, with Gomez
as its foreperson, found Rivera guilty of first-degree mur
der. A divided panel of the Appellate Court of Illinois
rejected Rivera’s challenge to the trial judge’s Batson
ruling and affirmed his conviction. 348 Ill. App. 3d 168,
810 N. E. 2d 129 (2004).
  The Supreme Court of Illinois accepted Rivera’s petition
for leave to appeal and remanded for further proceedings.
4                    RIVERA v. ILLINOIS

                      Opinion of the Court

221 Ill. 2d 481, 852 N. E. 2d 771 (2006). A trial judge, the
court held, may raise a Batson issue sua sponte only when
there is a prima facie case of discrimination. Concluding
that the record was insufficient to evaluate the existence
of a prima facie case, the court instructed the trial judge to
articulate the bases for his Batson ruling and, in particu
lar, to clarify whether the alleged discrimination was on
the basis of race, sex, or both. 221 Ill. 2d, at 515–516, 852
N. E. 2d, at 791.
   On remand, the trial judge stated that prima facie
evidence of sex discrimination—namely, counsel’s two
prior challenges to women and “the nature of [counsel’s]
questions”—had prompted him to raise the Batson issue.
App. 136. Counsel’s stated reasons for challenging Gomez,
the judge reported, convinced him that that “there had
been a purposeful discrimination against Mrs. Gomez
because of her gender.” Id., at 137.
   The case then returned to the Illinois Supreme Court.
Although that court disagreed with the trial judge’s as
sessment, it affirmed Rivera’s conviction. 227 Ill. 2d 1,
879 N. E. 2d 876 (2007). The Illinois High Court con
cluded “that the record fails to support a prima facie case
of discrimination of any kind.” Id., at 15, 879 N. E. 2d, at
884. Accordingly, the court determined, the trial judge
erred, first in demanding an explanation from Rivera’s
counsel, and next, in denying Rivera’s peremptory chal
lenge of Gomez. Ibid.
   Even so, the Illinois Supreme Court rejected Rivera’s
ultimate argument that the improper seating of Gomez
ranked as “reversible error without a showing of preju
dice.” Id., at 16, 879 N. E. 2d, at 885 (quoting Swain v.
Alabama, 380 U. S. 202, 219 (1965)). Citing this Court’s
guiding decisions, the Illinois court observed that “the
Constitution does not confer a right to peremptory chal
lenges.” 227 Ill. 2d, at 17, 879 N. E. 2d, at 885 (quoting
Batson, 476 U. S., at 91). Although “peremptory chal
                  Cite as: 556 U. S. ____ (2009)            5

                      Opinion of the Court

lenges are ‘one means of assuring the selection of a quali
fied and unbiased jury,’ ” the court explained, they are not
“indispensable to a fair trial.” 227 Ill. 2d, at 16, 879 N. E.
2d, at 885 (quoting Batson, 476 U. S., at 91).
   Accordingly, the court held, the denial of Rivera’s per
emptory challenge did not qualify as a structural error
requiring automatic reversal. See 227 Ill. 2d, at 19–20,
879 N. E. 2d, at 887 (citing Washington v. Recuenco, 548
U. S. 212, 218–219 (2006)). The court saw no indication
that Rivera had been “tried before a biased jury, or even
one biased juror.” 227 Ill. 2d, at 20, 879 N. E. 2d, at 887.
In that regard, the court stressed, Rivera did “not suggest
that Gomez was subject to excusal for cause.” Ibid.
   Relying on both federal and state precedents, the court
proceeded to consider whether it was “clear beyond a
reasonable doubt that a rational jury would have found
[Rivera] guilty absent the error.” Id., at 21, 879 N. E. 2d,
at 887 (quoting Neder v. United States, 527 U. S. 1, 18
(1999)). After reviewing the trial record, the court con
cluded that Gomez’s presence on the jury did not prejudice
Rivera because “any rational trier of fact would have
found [Rivera] guilty of murder on the evidence adduced
at trial.” 227 Ill. 2d, at 26, 879 N. E. 2d, at 890.
   Having held the error harmless beyond a reasonable
doubt, the court added that it “need not decide whether
the erroneous denial of a peremptory challenge is an error
of constitutional dimension in these circumstances.” Id.,
at 27, 879 N. E. 2d, at 891. This comment, it appears,
related to Rivera’s arguments that, even absent a free
standing constitutional entitlement to peremptory chal
lenges, the inclusion of Gomez on his jury violated his
Fourteenth Amendment right to due process of law.
   We granted certiorari, 554 U. S. __ (2008), to resolve an
apparent conflict among state high courts over whether
the erroneous denial of a peremptory challenge requires
automatic reversal of a defendant’s conviction as a matter
6                    RIVERA v. ILLINOIS

                     Opinion of the Court

of federal law. Compare Angus v. State, 695 N. W. 2d 109,
118 (Minn. 2005) (applying automatic reversal rule); State
v. Vreen, 143 Wash. 2d 923, 927–932, 26 P. 3d 236, 238–
240 (2001) (same), with People v. Bell, 473 Mich. 275, 292–
299, 702 N. W. 2d 128, 138–141 (2005) (rejecting auto
matic reversal rule and looking to state law to determine
the consequences of an erroneous denial of a peremptory
challenge); 227 Ill. 2d., at 15–27, 879 N. E. 2d, at 884–891
(case below). We now affirm the judgment of the Supreme
Court of Illinois.
                              II
   The Due Process Clause of the Fourteenth Amendment,
Rivera maintains, requires reversal whenever a criminal
defendant’s peremptory challenge is erroneously denied.
Rivera recalls the ancient lineage of the peremptory chal
lenge and observes that the challenge has long been
lauded as a means to guard against latent bias and to
secure “the constitutional end of an impartial jury and a
fair trial.” McCollum, 505 U. S., at 57. When a trial court
fails to dismiss a lawfully challenged juror, Rivera asserts,
it commits structural error: the jury becomes an illegally
constituted tribunal, and any verdict it renders is per se
invalid. According to Rivera, this holds true even if the
Constitution does not itself mandate peremptory chal
lenges, because criminal defendants have a constitution
ally protected liberty interest in their state-provided per
emptory challenge rights. Cf. Evitts v. Lucey, 469 U. S.
387, 393 (1985) (although “the Constitution does not re
quire States to grant appeals as of right to criminal defen
dants,” States that provide such appeals “must comport
with the demands of the Due Process and Equal Protection
Clauses”).
   The improper seating of a juror, Rivera insists, is not
amenable to harmless-error analysis because it is impossi
ble to ascertain how a properly constituted jury—here, one
                    Cite as: 556 U. S. ____ (2009)                  7

                        Opinion of the Court

without juror Gomez—would have decided his case. Thus,
he urges, whatever the constitutional status of peremptory
challenges, automatic reversal must be the rule as a mat
ter of federal law.
   Rivera’s arguments do not withstand scrutiny. If a
defendant is tried before a qualified jury composed of
individuals not challengeable for cause, the loss of a per
emptory challenge due to a state court’s good-faith error is
not a matter of federal constitutional concern. Rather, it
is a matter for the State to address under its own laws.
   As Rivera acknowledges, Brief for Petitioner 38, this
Court has consistently held that there is no freestanding
constitutional right to peremptory challenges. See, e.g.,
Martinez-Salazar, 528 U. S., at 311. We have character
ized peremptory challenges as “a creature of statute,” Ross
v. Oklahoma, 487 U. S. 81, 89 (1988), and have made clear
that a State may decline to offer them at all. McCollum,
505 U. S., at 57. See also Holland v. Illinois, 493 U. S.
474, 482 (1990) (dismissing the notion “that the require
ment of an ‘impartial jury’ impliedly compels peremptory
challenges”). When States provide peremptory challenges
(as all do in some form), they confer a benefit “beyond the
minimum requirements of fair [jury] selection,” Frazier v.
United States, 335 U. S. 497, 506 (1948), and thus retain
discretion to design and implement their own systems,
Ross, 487 U. S., at 89.1
   Because peremptory challenges are within the States’
province to grant or withhold, the mistaken denial of a
state-provided peremptory challenge does not, without
more, violate the Federal Constitution. “[A] mere error of
state law,” we have noted, “is not a denial of due process.”
——————
  1 See Dept. of Justice, Bureau of Justice Statistics, State Court Or

ganization 2004, pp. 228–232 (2006) (Table 41), http://www.ojp.usdoj.
gov/bjs/pub/pdf/sco04.pdf (as visited Mar. 27, 2009, and available in
Clerk of Court’s case file) (detailing peremptory challenge rules by
State).
8                   RIVERA v. ILLINOIS

                     Opinion of the Court

Engle v. Isaac, 456 U. S. 107, 121, n. 21 (1982) (internal
quotation marks omitted). See also Estelle v. McGuire,
502 U. S. 62, 67, 72–73 (1991). The Due Process Clause,
our decisions instruct, safeguards not the meticulous
observance of state procedural prescriptions, but “the
fundamental elements of fairness in a criminal trial.”
Spencer v. Texas, 385 U. S. 554, 563–564 (1967).
   The trial judge’s refusal to excuse juror Gomez did not
deprive Rivera of his constitutional right to a fair trial
before an impartial jury. Our decision in Ross is instruc
tive. Ross, a criminal defendant in Oklahoma, used a
peremptory challenge to rectify the trial court’s erroneous
denial of a for-cause challenge, leaving him with one fewer
peremptory challenge to use at his discretion. The trial
court’s error, we acknowledged, “may have resulted in a
jury panel different from that which would otherwise have
decided [Ross’s] case.” 487 U. S., at 87. But because no
member of the jury as finally composed was removable for
cause, we found no violation of Ross’s Sixth Amendment
right to an impartial jury or his Fourteenth Amendment
right to due process. Id., at 86–91.
   We encountered a similar situation in Martinez-Salazar
and reached the same conclusion. Martinez-Salazar, who
was tried in federal court, was entitled to exercise peremp
tory challenges pursuant to Federal Rule of Criminal
Procedure 24(b). His decision to use one of his peremptory
challenges to cure the trial court’s erroneous denial of a
for-cause challenge, we held, did not impair his rights
under that Rule. “[A] principal reason for peremptories,”
we explained, is “to help secure the constitutional guaran
tee of trial by an impartial jury.” 528 U. S., at 316. Hav
ing “received precisely what federal law provided,” and
having been tried “by a jury on which no biased juror sat,”
Martinez-Salazar could not “tenably assert any violation
of his . . . right to due process.” Id., at 307, 317.
   Rivera’s efforts to distinguish Ross and Martinez
                 Cite as: 556 U. S. ____ (2009)          9

                     Opinion of the Court

Salazar are unavailing. First, Rivera observes, the defen
dants in Ross and Martinez-Salazar did not challenge any
of the jurors who were in fact seated. In contrast, Rivera
attempted to exercise a peremptory challenge against a
specific person—Gomez—whom he perceived to be unfa
vorable to his cause. But, as Rivera recognizes, neither
Gomez nor any other member of his jury was removable
for cause. See Tr. of Oral Arg. 9. Thus, like the juries in
Ross and Martinez-Salazar, Rivera’s jury was impartial
for Sixth Amendment purposes. Rivera suggests that due
process concerns persist because Gomez knew he did not
want her on the panel. Gomez, however, was not privy to
the in camera discussions concerning Rivera’s attempt to
exercise a peremptory strike against her. See, supra, at 3.
We reject the notion that a juror is constitutionally dis
qualified whenever she is aware that a party has chal
lenged her. Were the rule otherwise, a party could cir
cumvent Batson by insisting in open court that a trial
court dismiss a juror even though the party’s peremptory
challenge was discriminatory. Or a party could obtain a
juror’s dismissal simply by making in her presence a
baseless for-cause challenge. Due process does not require
such counterintuitive results.
   Second, it is not constitutionally significant that the
seating of Gomez over Rivera’s peremptory challenge was
at odds with state law. The defendants in Ross and Mar
tinez-Salazar, Rivera emphasizes, were not denied their
peremptory-challenge rights under applicable law—state
law in Ross and the Federal Rules of Criminal Procedure
in Martinez-Salazar. But as we have already explained,
supra, at 7–8, errors of state law do not automatically
become violations of due process. As in Ross and Marti
nez-Salazar, there is no suggestion here that the trial
judge repeatedly or deliberately misapplied the law or
acted in an arbitrary or irrational manner. Martinez-
Salazar, 528 U. S., at 316; Ross, 487 U. S., at 91, n. 5.
10                  RIVERA v. ILLINOIS

                     Opinion of the Court

Rather, the trial judge’s conduct reflected a good-faith, if
arguably overzealous, effort to enforce the antidiscrimina
tion requirements of our Batson-related precedents. To
hold that a one-time, good-faith misapplication of Batson
violates due process would likely discourage trial courts
and prosecutors from policing a criminal defendant’s
discriminatory use of peremptory challenges. The Four
teenth Amendment does not compel such a tradeoff.
   Rivera insists that, even without a constitutional viola
tion, the deprivation of a state-provided peremptory chal
lenge requires reversal as a matter of federal law. We
disagree. Rivera relies in part on Swain, 380 U. S. 202,
which suggested that “[t]he denial or impairment of the
right [to exercise peremptory challenges] is reversible
error without a showing of prejudice.” Id., at 219. We
disavowed this statement in Martinez-Salazar, observing,
albeit in dicta, “that the oft-quoted language in Swain was
not only unnecessary to the decision in that case . . . but
was founded on a series of our early cases decided long
before the adoption of harmless-error review.” 528 U. S.,
at 317, n. 4. As our recent decisions make clear, we typi
cally designate an error as “structural,” therefore “re
quir[ing] automatic reversal,” only when “the error ‘neces
sarily render[s] a criminal trial fundamentally unfair or
an unreliable vehicle for determining guilt or innocence.’ ”
Recuenco, 548 U. S., at 218–219 (quoting Neder, 527 U. S.,
at 9). The mistaken denial of a state-provided peremptory
challenge does not, at least in the circumstances we con
front here, constitute an error of that character.
   The automatic reversal precedents Rivera cites are
inapposite. One set of cases involves constitutional errors
concerning the qualification of the jury or judge. In Bat
son, for example, we held that the unlawful exclusion of
jurors based on race requires reversal because it “violates
a defendant’s right to equal protection,” “unconstitution
ally discriminate[s] against the excluded juror,” and “un
                     Cite as: 556 U. S. ____ (2009)                  11

                         Opinion of the Court

dermine[s] public confidence in the fairness of our system
of justice.” 476 U. S., at 86, 87. Similarly, dismissal of a
juror in violation of Witherspoon v. Illinois, 391 U. S. 510
(1968),2 we have held, is constitutional error that requires
vacation of a death sentence. See Gray v. Mississippi, 481
U. S. 648 (1987). See also Gomez v. United States, 490
U. S. 858, 876 (1989) (“Among those basic fair trial rights
that can never be treated as harmless is a defendant’s
right to an impartial adjudicator, be it judge or jury.”
(internal quotation marks omitted)).
   A second set of cases involves circumstances in which
federal judges or tribunals lacked statutory authority to
adjudicate the controversy. We have held the resulting
judgment in such cases invalid as a matter of federal law.
See, e.g., Nguyen v. United States, 539 U. S. 69 (2003);
Wingo v. Wedding, 418 U. S. 461 (1974). Nothing in these
decisions suggests that federal law renders state-court
judgments void whenever there is a state-law defect in a
tribunal’s composition. Absent a federal constitutional
violation, States retain the prerogative to decide whether
such errors deprive a tribunal of its lawful authority and
thus require automatic reversal. States are free to decide,
as a matter of state law, that a trial court’s mistaken
denial of a peremptory challenge is reversible error per se.
Or they may conclude, as the Supreme Court of Illinois
implicitly did here, that the improper seating of a compe
tent and unbiased juror does not convert the jury into an
ultra vires tribunal; therefore the error could rank as
harmless under state law.
   In sum, Rivera received precisely what due process
required: a fair trial before an impartial and properly
——————
   2 Under Witherspoon v. Illinois, 391 U. S. 510 (1968), “a sentence of

death cannot be carried out if the jury that imposed or recommended it
was chosen by excluding veniremen for cause simply because they
voiced general objections to the death penalty or expressed conscien
tious or religious scruples against its infliction.” Id., at 522.
12                  RIVERA v. ILLINOIS

                     Opinion of the Court

instructed jury, which found him guilty of every element of
the charged offense.
                      *    *    *
  For the reasons stated, the judgment of the Supreme
Court of Illinois is
                                              Affirmed.
