In 2024, the South Carolina Court of Appeals, in the case of In the Matter of Shawn T. Daily, 443 S.C. 557, 905 S.E.2d 310 (Ct. App. 2024), held that the results of a penile plethysmograph (PPG) test are inadmissible as unreliable. Blogging about Daily at the time, I noted that such tests were often used in family court, especially child abuse proceedings, but that the issue of their admissibility remained subject to dispute. I noted Daily seemed to rule such tests inadmissible but also noted that, absent a definitive ruling from the Supreme Court, the answer was not 100% clear.
As of May 13, 2026, the answer is 100% clear. In the case of In the Matter of the Care and Treatment of Andy Eugene Hyman, the South Carolina Supreme Court held that such tests were inadmissible in the context of sexually violent predator commitment proceedings. The unanimous court’s reasoning was that PPG tests were not standardized and did not meet three of the four criteria of reliability.
At least in its current form the PPG test is too unreliable to be admissible in South Carolina court proceedings.
