Williams v. Illinois Resource Page (Introduction and Overview)

About The Williams v. Illinois Resource Page


DOJ Building The Williams v. Illinois Resource Page provides background and key links on this significant Confrontation Clause case decided by the U.S. Supreme Court on June 18, 2012. See Williams v. Illinois, 567 U.S. _, 132 S.Ct. 2221, 183 L.Ed.2d 89 (June 18, 2012) (No. 10-8505).

On December 6, 2011, the Supreme Court heard argument in a case that presents questions about the scope of expert testimony which is based on the conclusions of a non-testifying expert under the Confrontation Clause. See Williams v. Illinois (No. 10-8505). In addition to the overview below, other information on the Williams v. Illinois Resource Page case includes Key Briefs and Other Materials, and coverage in the Federal Evidence Blog.



Issue Presented

The issue presented in Williams v. Illinois (No. 10-8505) is:

Whether a state rule of evidence allowing an expert witness to testify about the results of DNA testing performed by non-testifying analysts, where the defendant has no opportunity to confront the actual analysts, violates the Confrontation Clause.


Summary For: Williams v. Illinois (No. 10-8505)


  • Summary Facts: Defendant Williams was arrested on another offense about six months after a sexual assault had been committed. The defendant provided a blood sample. A forensic scientist entered a deoxyribonucleic acid (DNA) profile into the state crime lab database. A Cellmark Diagnostics Laboratory conducted testing on the victim sample and obtained a male DNA profile. A forensic biologist testified at trial about the results of the DNA tests. She concluded that there was a DNA match between the blood sample obtained from the defendant and the semen sample obtained from the victim. No witness from Cellmark testified about the results from the victim sample. The Cellmark DNA test report was not admitted at trial. In a bench trial, defendant Williams was convicted of aggravated criminal sexual assault, aggravated kidnapping and aggravated robbery. See People v. Williams, 238 Ill.2d 125, 345 Ill.Dec. 425, 939 N.E.2d 268 (July 15, 2010).

  • Claim On Appeal: On appeal, the petitioner claimed his Confrontation Clause rights were violated by the admission of expert testimony which relied on the conclusions of a non-testifying expert concerning the DNA profile obtained from the semen sample. He claimed that he was denied the right to confront and cross-examine the non-testifying analyst about the DNA test and results that were obtained.
  • Lower Court Action: The Illinois Supreme Court affirmed the conviction. The state supreme court held that Confrontation Clause concerns were not implicated since the expert testimony about the Cellmark report was not testimonial. The expert testimony “disclosed the underlying facts from Cellmark’s report for the limited purpose of explaining the basis for her opinion on the critical issue concerning whether there was a DNA match between the defendant’s blood sample and the semen sample recovered from [victim] L.J. By allowing the expert to reveal the information for this purpose alone, it undoubtedly aided the judge, sitting as the factfinder, in assessing the value of [expert] Lambatos’ opinion.” The defendant was able to cross-examine the expert about the basis for her conclusion. People v. Williams, 238 Ill.2d 125, 345 Ill.Dec. 425, 939 N.E.2d 268, 282 (July 15, 2010).
  • Certiorari Review: On June 28, 2011, the Supreme Court granted certiorari review of the state court judgment.
  • Oral Argument and Transcript: On December 6, 2011, the Supreme Court heard oral argument on the case. See Williams v. Illinois (No. 10-8505) Oral Argument Transcript; Listen to the Oral Argument (Audio File).
  • Decision: On June 18, 2012, in a plurality holding, the Supreme Court held that the expert testimony did not violate the Confrontation Clause in a plurality ruling. First, "When an expert testifies for the prosecution in a criminal case, the defendant has the opportunity to cross-examinethe 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 theirtruth and thus fall outside the scope of the ConfrontationClause. Applying this rule to the present case, we conclude that the expert’s testimony did not violate the SixthAmendment." Second, the expert testimony was not "testimonial" under the Sixth Amendment. See Williams v. Illinois, 567 U.S. _, 132 S.Ct. 2221, 183 L.Ed.2d 89 (June 18, 2012) (No. 10-8505).
  • Supreme Court Docket: Docket.
  • Additional Information: For more information, see Key Briefs and Other Materials; and blog posts from the Federal Evidence Blog discussing the Williams v. Illinois case (available here).

Williams v. Illinois Oral Argument audio




Federal Rules of Evidence
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