United States v. Semrau - 693 F.3d 510 (6th Cir. 2012)

Rule:

Fed. R. Evid. 702 confers a gatekeeping role on trial judges to ensure that an expert's testimony both rests on a reliable foundation and is relevant to the task at hand. The inquiry is a flexible one focused on principles and methodology. There is no definitive checklist or test for balancing the liberal admissibility standards for relevant evidence and the need to exclude misleading junk science. However, the United States Supreme Court did identify four factors that normally bear on the inquiry: (1) whether a theory or technique can be or has been tested; (2) whether the theory or technique has been subjected to peer review and publication; (3) the known or potential rate of error in using a particular scientific technique and the standards controlling the technique's operation; and (4) whether the theory or technique has been generally accepted in the particular scientific field. 

Facts:

Dr. Lorne Semrau appealed his conviction of three counts of healthcare fraud in violation of 18 U.S.C. § 1347. Among other issues, Dr. Semrau argued—on a matter of first impression in any jurisdiction—that results from a functional magnetic resonance imaging ("fMRI") lie detection test should have been admitted to prove the veracity of his denials of wrongdoing.

Issue:

Did the district court abuse its discretion in excluding the fMRI evidence under Fed. R. Evid. 702?

Answer:

No.

Conclusion:

The court held that the district court did not abuse its discretion in excluding the fMRI evidence under Fed. R. Evid. 702 because the technology had not been fully examined in real world settings, and the testing administered to Dr. Semrau was not consistent with tests done in research studies. The court also ruled that the testimony was independently inadmissible under Fed. R. Evid. 403 because the prosecution did not know about the test before it was conducted, constitutional concerns caution against admitting lie detection tests to bolster witness credibility, and the test results did not purport to indicate whether Dr. Semrau was truthful about any single statement. The evidence was sufficient to support the conviction, and the district court did not err in failing to include defendant's proposed instructions in the jury charge.