Criminal trials may see defendants calling expert witnesses for strengthening their plea of innocence or for arguing for diminished responsibility. The case State of Minnesota v. Jay Dean Uldrych (2015 Minn. App. Unpub. LEXIS 209) was an instance where the defendant, accused of second-degree criminal sexual conduct, took the plea that he suffered from a sleep disorder condition known as sexsomnia at the time of the alleged offence, which should mitigate his responsibility for the same, and took the help of an expert witness for establishing this.
The defendant’s expert had testified during the trial that the defendant had been diagnosed with sexsomnia, which exhibits sexual behavior while sleeping. The expert, based on his review of the defendant’s sleep study and supporting materials, the incident that formed the basis for the criminal charges resulted from a sexsomnia-related episode. The district court refused to include the expert testimony on the ground that there was insufficient foundational reliability to admit the evidence at trial because the expert did not comply with relevant safeguards and controls in formulating his diagnosis.
Hearing the defendant’s appeal, the Court of Appeals of Minnesota agreed with the district court, reasoning that the expert’s testimony did not meet the second prong of the Frye-Mack standard – foundtional reliability, i.e., whether the methodology with the aid of which the expert witness has arrived at his opinion conforms with appropriate standards and controls. From the literature submitted by the defendant to the district court, the Court of Appeals noted the necessary tests and procedures for an accurate sexsomnia diagnosis:
“These tests include narcotics screening, a sleep study conducted over multiple nights with the subject’s normal bed partner, a daytime sleep latency test, general medical evaluation, a sleep disorder questionnaire, clinical interview of the subject and his or her bed partner, clinical evaluation for specific physical signs of sleep disorders, a neurological and psychiatric evaluation, and a neuroimaging.”
However, the Court found that the defendant’s sleep study, which was performed by a different physician, lasted for less than seven hours, without his normal bed partner, and that the expert did not conduct formal medical evaluations, neurological screenings, or clinical interviews with appellant or his bed partner. Such non-compliance with the requisite controls robbed the expert testimony of its reliability, concluded the Court, upholding the opinion of the district court.