A hearing under way in a federal court in Tennessee today represents the most formal legal test yet for the use of lie-detection technology based on functional magnetic resonance imaging (fMRI) of brain activity.
The hearing is likely to reveal more details about the methodology used in commercial fMRI lie-detection services. Until now, relatively little information has been publicly available. It could also establish an important precedent for future cases involving this controversial technology.
The defendant in the case is a psychologist named Lorne Semrau, who is accused of defrauding Medicare and Medicaid. As reported last week by Wired Science , Semrau claims he had no intention to do so and has retained the services of Cephos, a Massachusetts-based company that sells fMRI-based lie-detection services, to help establish that he is telling the truth. Court documents indicate that Semrau's lawyer introduced a motion for Cephos CEO Steven Laken to testify as an expert witness on his behalf.
Today, Judge Tu Pham will hear testimony for and against the inclusion of the fMRI evidence in what's known as a Daubert hearing, which takes its name from a 1995 Supreme Court case that established guidelines for the admissibility of expert testimony in federal cases. These include factors such as the error rates associated with a given technology, whether it is supported by published research, and whether it is accepted by the scientific community.
ScienceInsider has learned that the prosecution has lined up two experts to testify on the limitations of fMRI lie detection.
They are neurologist and veteran neuroimaging researcher Marcus Raichle of Washington University in St. Louis and Peter Imrey, a biostatistician at the Cleveland Clinic Foundation. Both served on a 2003 National Academy of Sciences panel that issued a critical report  on the scientific validity polygraph lie detection.
Whichever way the judge decides, it could establish an important precedent, says Stanford University law professor Henry Greely. (Greely has advised the prosecution in the Semrau case.) "As it is a trial level court, it would not bind other judges, the way an appellate decision would bind the lower courts," Greely wrote in an e-mail. "But it could have substantial persuasive force."
*Correction: Defendant Lorne Semrau was originally identified as a psychiatrist; he is actually a psychologist.