                            In the
 United States Court of Appeals
              For the Seventh Circuit
                         ____________

No. 02-3565
JOEL BUIE,
                                           Petitioner-Appellant,
                               v.

EUGENE MCADORY, WARDEN,
MENARD CORRECTIONAL CENTER,
                                          Respondent-Appellee.
                         ____________
       Appeal from the United States District Court for the
         Northern District of Illinois, Eastern Division.
            No. 97 C 1034—David H. Coar, Judge.
                         ____________
    ARGUED AUGUST 5, 2003—DECIDED AUGUST 25, 2003
                     ____________


  Before EASTERBROOK, ROVNER, and DIANE P. WOOD,
Circuit Judges.
  EASTERBROOK, Circuit Judge. Someone bludgeoned
Bennie Ervin to death in her home and stole her jewelry
plus other valuables. A jury convicted Joel Buie of these
crimes; the judge sentenced him to life imprisonment. The
evidence supporting this verdict includes Buie’s confes-
sion, the fact that he was hard up for money (shortly af-
ter the murder he tried to exchange a gold chain for co-
caine, and Ervin’s husband testified that she always
wore such a chain), and the fact that there were no signs
of forced entry. Buie and Ervin lived a few doors apart,
and he had agreed to install a hook for a flower pot in her
2                                              No. 02-3565

home. The prosecutor’s theory is that, when Ervin admit-
ted Buie for this purpose, he pushed her down the base-
ment stairs and used the hammer on her rather than the
hardware. Police found a metal hook on the floor near
the bottom of the stairs.
  Though Buie later contended that his confession to
this sequence of events had been obtained unlawfully, the
state judge found that Buie lied about what had occurred
in the police station. He contended, for example, that
the police severely beat him, but medical personnel found
no bruises or scratches on his body. The confession also
was consistent with statements of Buie’s girlfriend and
a neighbor’s recollection that Buie related that he had
visited the Ervin home to install a hook.
  The state’s appellate court affirmed Buie’s conviction
and sentence. People v. Buie, 238 Ill. App. 3d 260, 606
N.E.2d 279 (1st Dist. 1992). A collateral attack in state
court was abandoned after counsel concluded that it
was frivolous. The federal district judge denied Buie’s
petition for relief under 28 U.S.C. §2254. United States
ex rel. Buie v. Page, 2002 U.S. Dist. LEXIS 16034 (N.D. Ill.
Aug. 22, 2002). A motions panel declined to vacate the
district judge’s certificate of appealability; although the
panel concluded that the certificate failed to identify any
substantial constitutional issue, see 28 U.S.C. §2253(c)(2),
it held that there was some potential for constitutional
argument notwithstanding the certificate’s defects. Buie
v. McAdory, 322 F.3d 980 (7th Cir. 2003).
  Buie’s principal argument is that the trial judge vio-
lated the due process clause by permitting an expert wit-
ness to overstate the strength of her conclusion. Police
found some strands of hair on Ervin’s clothing and among
shards of glass on the basement floor. (Ervin had been
beaten with a bottle as well as a hammer.) Maria Pulling,
who Buie acknowledges to be a legitimate expert in hair
No. 02-3565                                               3

analysis, testified that the hair “exhibited characteristics
that were the same as Joel Buie’s head hair standards.”
After detailing for the jury the respects in which the
hairs matched, Pulling testified: “Within a reasonable
degree of scientific certainty I would say that the hair
came from Joel Buie.” She told the jury that her methods
did not exclude the possibility that the hairs came
from someone else but that she thought this probability
low. She repeated these limitations on cross-examina-
tion. Buie presented a hair expert of his own; this expert
testified that Pulling had overstated the degree of confi-
dence allowed by tests available at the time. He did not,
however, examine the hairs himself, conclude that they
came from someone other than Buie, or even opine that
the set of potential donors for these strands was particu-
larly large.
  According to Buie, the Constitution forbids any expert
witness to misstate scientific conclusions in a criminal
prosecution. It is far from clear that Pulling did this;
she and the defense expert debated the accuracy of hair
analysis, and Buie does not cite any scientific literature
establishing that Pulling was in the wrong. “Reasonable
degree of scientific certainty” is a plastic phrase. Let us
assume, however, that Buie’s expert had the better of the
argument. Still, to obtain collateral relief, Buie must
show that the state’s decision “was contrary to, or in-
volved an unreasonable application of, clearly established
Federal law, as determined by the Supreme Court of the
United States”. 28 U.S.C. §2254(d)(1). No decision of the
Supreme Court “clearly establishes” that experts (or any
other witnesses) must be right; the constitutional rule
is that the defendant is entitled to a trial that will en-
able jurors to determine where the truth lies. That a
witness may give false or mistaken testimony therefore
is not an independent constitutional violation. See, e.g.,
Herrera v. Collins, 506 U.S. 390, 398-405 (1993). What the
4                                                No. 02-3565

Constitution provides is assurance that evidence may be
tested by cross-examination and by contrary proofs.
Whether a given expert witness overstated her conclu-
sion is mete for cross-examination, and no one impaired
Buie’s ability to elicit from her just how likely (or unlikely)
a “reasonable degree of scientific certainty” was in her
vocabulary. The state paid for an expert witness to evalu-
ate the issue and testify on behalf of the defense. See
Ake v. Oklahoma, 470 U.S. 68 (1985).
  The state’s appellate court did not apply any of these
principles unreasonably in holding that the jury was
entitled to hear Pulling’s testimony. And if state law
contains the principle for which Buie contends, and the
state court therefore should have struck this portion
of Pulling’s testimony—well, an error of state evidence
law cannot be the basis of federal collateral relief.
See Estelle v. McGuire, 502 U.S. 62 (1991). See also
Gilmore v. Taylor, 508 U.S. 333 (1993). Although the fed-
eral Constitution may be offended when probative excul-
patory evidence is pointlessly excluded, see Chambers v.
Mississippi, 410 U.S. 284 (1973), no comparable rule con-
demns the admission of evidence that the defendant
deems untrustworthy, as long as the state affords the de-
fendant the means to demonstrate its weaknesses (and
its use does not violate the confrontation clause). Infor-
mants may be lying, eyewitnesses may be tricked by
their own memories, and experts may produce flawed
analyses. The tools of the adversary process supply the
means to expose these testimonial shortcomings. The
Constitution does not impose Fed. R. Evid. 702 on the
states, let alone require that federal courts scrutinize line
by line the state-court testimony of experts conceded to
be competent.
  Although the state must not withhold exculpatory
evidence or use testimony that the prosecutor knows
is false, see Giglio v. United States, 405 U.S. 150 (1972);
No. 02-3565                                                5

Brady v. Maryland, 373 U.S. 83 (1963), these closely
related decisions do not offer Buie any support. (The dis-
trict judge thought that arguments based on Giglio had
been forfeited in state court, while arguments based on
Brady had been preserved. Yet these two decisions re-
flect the same fundamental principle, which therefore
is open to consideration in this collateral attack.) Illinois
did not try to conceal the limitations of hair analysis.
Scientific literature is published for all to read, and the
state furnished Buie with an expert to assist in the under-
standing and application of this knowledge. If Pulling
should have been more cautions than she was, this was
known to the defense as well as to the prosecutor. Giglio
does not license a federal court to determine whether
particular testimony in a state trial was good or bad
substantively; that decision condemns only subornation
of perjury. The Illinois appellate court did not act unrea-
sonably in concluding that the prosecutor’s behavior was
above board. He asked a series of questions that en-
abled Pulling to describe the tests she performed and the
conclusions she drew. Buie does not contend that the
prosecutor had, but concealed, some private knowledge
suggesting that Pulling had not performed the tests
about which she testified, or that she did not actually
hold the conclusions she articulated. Thus we are back
to the claim that Pulling made a statement more confi-
dent than the science supports, and that is neither a
Brady nor a Giglio problem. It is just a reason why defen-
dants have the right to cross-examine witnesses and
present evidence of their own.
  Buie’s other contention is that his lawyer in the state
proceedings furnished constitutionally ineffective assis-
tance. This claim was defaulted, as the district judge
held. It was not presented to the state judiciary on direct
appeal or pursued to conclusion on collateral attack. See
O’Sullivan v. Boerckel, 526 U.S. 838 (1999). Buie does not
6                                             No. 02-3565

contend that he has any cause for this omission. See
Wainwright v. Sykes, 433 U.S. 72 (1977). Instead, he says,
this claim should be adjudicated despite the default in
order to vindicate the rights of a person who is actually
innocent. See Herrera, 506 U.S. at 404; Sawyer v. Whitley,
505 U.S. 333 (1992). Yet it is hard to see how one who
has confessed can assert actual innocence. Buie’s chal-
lenge to that confession was rejected in state court on
factual grounds that are uncontested today.
  According to Buie, his innocence is established by the
fact that his fingernails were intact when he was ar-
rested. This seemingly mundane fact acquires signifi-
cance, Buie’s lawyer insists, when combined with the
fact that a fingernail fragment was retrieved from the
bottom of the basement stairs in Ervin’s house, tested, and
found not to be Ervin’s. If it was not Ervin’s, and could
not have been his, then someone else must have com-
mitted the crime, Buie contends. The problem with this
argument is that the record does not show how old the
fragment was when collected and how many other people
may have broken a fingernail in the Ervin basement
within the available time. Without that information, the
fact that it could not have come from Buie on the day of
the murder reveals nothing about who committed that
crime.
  Nothing else in the record implies actual innocence. We
say this cognizant of the fact that the record in this col-
lateral attack is only a subset of the record assembled
in state court. It contains some pages of the transcript,
but not the full thing. At oral argument, Buie’s lawyer
said that he had made informal inquiries and been told
that much of the transcript had been lost in the lengthy
time (more than a decade) since the trial, and that the
court reporter was unavailable to recreate it. At this
point counsel let matters drop. He did not ask the fed-
eral judge to require the state to locate or recreate a
No. 02-3565                                             7

complete transcript, nor did he raise this as an issue
on appeal (which, given the lack of request in the dis-
trict court, could not have been much of an appellate
issue). A defendant who asserts actual innocence as a
reason to excuse a procedural default must demonstrate
innocence; the burden is his, not the state’s, for the
state has the benefit of the jury’s verdict. See Schlup v.
Delo, 513 U.S. 298, 324-38 (1995). Congress codified the
requirement in 28 U.S.C. §2254(e)(2)(B), which says that,
when a prisoner fails to develop the factual basis of a
position in state court (as Buie failed to develop his
ineffective-assistance claim) and an evidentiary hearing
in federal court would be necessary to prevail, the de-
fault may be overcome only if “the facts underlying the
claim would be sufficient to establish by clear and con-
vincing evidence that but for constitutional error, no
reasonable factfinder would have found the applicant
guilty of the underlying offense.” Buie could not prevail
without an evidentiary hearing into his ineffective-assis-
tance claim, yet he has not come close to establishing
innocence by clear and convincing evidence. It was not
the task of the district judge (or this court) to attempt
that task for him by augmenting the record, when Buie
has been content to receive a decision on the record as
it stands.
                                               AFFIRMED

A true Copy:
      Teste:

                       ________________________________
                       Clerk of the United States Court of
                         Appeals for the Seventh Circuit


                  USCA-02-C-0072—8-25-03
