delivered the opinion of the Court.
This case presents the question whether a criminal defendant’s federal constitutional rights are violated by an evidence rule under which the defendant may not introduce proof of third-party guilt if the prosecution has introduced forensic evidence that, if believed, strongly supports a guilty verdict.
I
On the morning of December 3Í, 1989, 86-year-old Mary Stewart was beaten, raped, and robbed in her home. She
*322
later died of complications stemming from her injuries. Petitioner was convicted by a South Carolina jury of murder, first-degree criminal sexual conduct, first-degree burglary, and robbery, and he was sentenced to death.
State
v.
Holmes,
320 S. C. 259, 262,
At the second trial, the prosecution relied heavily on the following forensic evidence:
“(1) [Petitioner’s] palm print was found just above the door knob on the interior side of the front door оf the victim’s house; (2) fibers consistent with a black sweatshirt owned by [petitioner] were found on the victim’s bed sheets; (3) matching blue fibers were found on the victim’s pink nightgown and on [petitioner’s] blue jeans; (4) microscopically consistent fibers were found on the pink nightgown and on [petitioner’s] underwear; (5) [petitioner’s] underwear contained a mixture of DNA from two individuals, and 99.99% of the population other than [petitioner] and the victim were excluded as contributors to that mixture; and (6) [petitioner’s] tank top was found to contain a mixture of [petitioner’s] blood and the victim’s blood.” Id., at 343,605 S. E. 2d, at 24 .
In addition, the prosecution introduced evidence that petitioner had been seen neаr Stewart’s home within an hour of the time when, according to the prosecution’s evidence, the attack took place.
Id.,
at 337-338, 343,
As a major part of his defense, petitioner attempted to undermine the State’s forensic evidence by suggesting that it had been contaminated and that certain law enforcement officers had engaged in a plot to frame him.
Id.,
at 339,
Petitioner also sought to introduce proof that another man, Jimmy McCaw White, had attacked Stewart. 361 S. C., at 340,
The trial court excluded petitioner’s third-party guilt evidence citing
State
v.
Gregory,
198 S. C. 98,
II
“[Sjtate and federal rulemakers have broad latitude under the Constitution to establish rules excluding evidence from criminal trials.”
United States
v.
Scheffer,
This Court’s cases contain several illustrations of “arbitrary” rules,
i. e.,
rules that excluded important defense evidence but that did not serve any legitimate interests. In
Washington
v.
Texas,
A similar constitutional violation occurred in Chambers v. Mississippi, supra. A murder defendant called as a witness a man named McDonald, who had previously confessed to the murder. When McDonald repudiated the confession оn the stand, the defendant was denied permission to examine McDonald as an adverse witness based on the State’s “ ‘voucher’ rule,” which barred parties from impeaching their own witnesses. Id., at 294. In addition, because the state hearsay rule did not include an exception for statements against penal interest, the defendant was not permitted to introduce evidence that McDonald had made self-incriminating statements to three other persons. Noting that the State had not even attempted to “defend” or “explain [the] underlying rationale” of the “voucher rule,” id., at 297, this Court held that “the exclusion of [the evidence of McDonald’s out-of-court statеments], coupled with the State’s refusal to permit [the defendant] to cross-examine McDonald, denied him a *326 trial in accord with traditional and fundamental standards of due process,” id., at 302.
Another arbitrary rule was held unconstitutional in Crane v. Kentucky, supra. There, the defendant was prevented from attempting to show at trial that his confession was unreliable because of the circumstances under which it was obtained, and neither the State Supreme Court nor the prosecution “advanced any rational justification for the wholesale exclusion of this body of potentially exculpatory evidence.” Id., at 691.
In Rock v. Arkansas, supra, this Court held that a rule prohibiting hypnotically refreshed testimony was unconstitutional because “[wjholesale inadmissibility оf a defendant’s testimony is an arbitrary restriction on the right to testify in the absence of clear evidence by the State repudiating the validity of all post-hypnosis recollections.” Id., at 61. By contrast, in Scheffer, supra, we held that a rule excluding all polygraph evidence did not abridge the right to present a defense because the rule “serve[d] several lеgitimate interests in the criminal trial process,” was “neither arbitrary nor disproportionate in promoting these ends,” and did not “implicate a sufficiently weighty interest of the defendant.” Id., at 309.
While the Constitution thus prohibits the exclusion of defense evidence under rules that serve no legitimate purpose or that are disproportionаte to the ends that they are asserted to promote, well-established rules of evidence permit trial judges to exclude evidence if its probative value is outweighed by certain other factors such as unfair prejudice, confusion of the issues, or potential to mislead the jury. See,
e. g.,
Fed. Rule Evid. 403; Uniform Rule of Evid. 45 (1953); ALI, Model Code of Evidence Rule 303 (1942); 3 J. Wigmore, Evidence §§ 1863, 1904 (1904). Plainly referring to rules of this type, we have stated that the Constitution permits judges “to exclude evidence that is ‘repetitive ..., only marginally relevant’ or poses an undue risk of ‘harassment, prej
*327
udice, [or] confusion of the issues.’”
Crane,
A specific application of this principle is found in rules regulating the admission of evidence proffered by criminal defendants to show that someone else committed the crime with which they are charged. See, e. g., 41 C. J. S., Homicide §216, pp. 56-58 (1991) (“Evidence tending to show the commission by another person of the crime charged may be introduced by accused when it is incоnsistent with, and raises a reasonable doubt of, his own guilt; but frequently matters offered in evidence for this purpose are so remote and lack such connection with the crime that they are excluded”); 40A Am. Jur. 2d, Homicide §286, pp. 136-138 (1999) (“[T]he accused may introduce any legal evidence tending to prove that another person may have committed the crime with which the defendant is charged .... [Such evidence] may be excluded where it does not sufficiently connect the other person to the crime, as, for example, where the evidence is speculative or remote, or does not tend to prove or disprove a material fact in issue at the defendant’s trial” (footnotes omitted)). Such rules are widely accepted, * and neither petitioner nor his amici challenge them here.
*328 In Gregory, the South Carolina Supreme Court adopted and applied a rule apparently intended to be of this type, given the court’s references to the “applicable rule” from Corpus Juris and American Jurisprudence:
“ ‘[Ejvidence offerеd by accused as to the commission of the crime by another person must be limited to such facts as are inconsistent with his own guilt, and to such facts as raise a reasonable inference or presumption as to his own innocence; evidence which can have (no) other effect than to cast a bare suspicion upon another, or to raise a conjectural inference as to the commission of the crime by another, is not admissible. . . . [Bjefore such testimony can be received, there must be such proof of connection with it, such a train of facts or circumstances, as tends clearly to point out such other person аs the guilty party.’” 198 S. C., at 104-105,16 S. E. 2d, at 534-535 (quoting 16 C. J., Criminal Law §1085, p. 560 (1918), and 20 Am. Jur., Evidence §265, p. 254 (1939); footnotes omitted).
In
Gay
and this case, however, the South Carolina Supreme Court radically changed and extended the rule. In
Gay,
after recognizing the standard applied in
Gregory,
the court stated that “[i]n view of the strong evidence of appellant’s guilt — especially the forensic evidence— . . . the proffered evidencе ... did not raise
‘a
reasonable inference’ as to
*329
appellant’s own innocence.” 343 S. C., at 550,
Under this rule, the trial judge does not focus on the probative value or the potential adverse effects of admitting the defense evidence of third-party guilt. Instead, the critical inquiry concerns the strength of the prosecution’s case: If the prosecution’s case is strong enough, the evidence of third-party guilt is excluded еven if that evidence, if viewed independently, would have great probative value and even if it would not pose an undue risk of harassment, prejudice, or confusion of the issues.
Furthermore, as applied in this case, the South Carolina Supreme Court’s rule seems to call for little, if any, examination of the credibility of the prosecution’s witnesses or the reliability of its evidence. Here, for example, the defense strenuously claimed that the prosecution’s forensic evidence was so unreliable (due to mishandling and a deliberate plot to frame petitioner) that the evidence should not have even been admitted. The South Carolina Suрreme Court responded that these challenges did not entirely “eviscerate” the forensic evidence and that the defense challenges went to the weight and not to the admissibility of that evidence.
Id.,
at 343, n. 8,
*330 Interpreted in this way, the rule applied by the State Supreme Court does not rationally serve the end that the Gregory rule and its analogues in other jurisdictions were designed to promotе, i. e., to focus the trial on the central issues by excluding evidence that has only a very weak logical connection to the central issues. The rule applied in this case appears to be based on the following logic: Where (1) it is clear that only one person was involved in the commission of a particular crimе and (2) there is strong evidence that the defendant was the perpetrator, it follows that evidence of third-party guilt must be weak. But this logic depends on an accurate evaluation of the prosecution’s proof, and the true strength of the prosecution’s proof cannot be assessed without considering challengеs to the reliability of the prosecution’s evidence. Just because the prosecution’s evidence, if credited, would provide strong support for a guilty verdict, it does not follow that evidence of third-party guilt has only a weak logical connection to the central issues in the case. And where the credibility of the prosecution’s witnesses or the reliability of its evidence is not conceded, the strength of the prosecution’s case cannot be assessed without making the sort of factual findings that have traditionally been reserved for the trier of fact and that the South Carolina courts did not purport to make in this case.
The rule applied in this case is no more logical than its converse would be, i. e., a rule barring the prosecution from introducing evidence of a defendant’s guilt if the defendant is able to proffer, at a pretrial hearing, evidence that, if believed, strongly supports a verdict of not guilty. In the present case, for example, petitioner proffered еvidence that, if believed, squarely proved that White, not petitioner, was the perpetrator. It would make no sense, however, to hold that this proffer precluded the prosecution from introducing its evidence, including the forensic evidence that, if credited, provided strong proof of petitioner’s guilt.
*331
The point is that, by evaluating the strength of only one party’s evidence, no logical conclusion can be reached regarding the strength of contrary evidence offered by the other side to rebut or cast doubt. Because the rule applied by the State Supreme Court in this case did not heed this point, the rule is “arbitrary” in the sense that it doеs not rationally serve the end that the
Gregory
rule and other similar third-party guilt rules were designed to further. Nor has the State identified any other legitimate end that the rule serves. It follows that the rule applied in this case by the State Supreme Court violates a criminal defendant’s right to have
‘“a
meaningful opportunity to present a complete defense.’”
Crane,
Ill
For these reasons, we vacate the judgment of the South Carolina Supreme Court and remand the case for further proceedings not inconsistent with this opinion.
It is so ordered.
Notes
See,
e. g., Smithart
v.
State,
