In these matters, the court considered the scientific reliability of expert testimony that shaking alone can cause the injuries associated with shaken baby syndrome (SBS), also known as abusive head trauma (AHT). The State sought to admit the testimony to prove aggravated assault and child endangerment charges against defendants Darryl Nieves and Michael Cifelli, fathers of infant sons who exhibited associated symptoms while in their respective fathers' care. Following a hearing in the Nieves matter pursuant to Frye v. United States, 293 F. 1013 (D.C. Cir. 1923), the trial judge concluded that expert testimony of shaking-only SBS/AHT was not scientifically reliable and barred admission of the evidence at trial. The trial judge in the Cifelli matter adopted the finding.
The court affirmed the judge's decision in Nieves, holding that the State failed to establish SBS/AHT's general acceptance within the medical community through expert testimony, supporting authoritative scientific studies, and judicial opinions. Where, as here, the underlying theory integrates multiple scientific disciplines, the proponent must establish cross-disciplinary validation to establish reliability. The State failed to do that here. Despite its seeming acceptance in the pediatric medical community, the evidence showed a real dispute surrounding the hypothesis that the biomechanical principles underlying SBS/AHT actually supported the conclusion that shaking only can cause the injuries associated with SBS/AHT.