ARTICLE: "General Acceptance, Reliability and Disagreement: A case study of "Shaken Baby Syndrome," by Jules Epstein, published on October 28, 2026 by The American Bar Association, in its Fall 2026, edition. (Julius Epstein: Temple University School of Law);
SUMMARY: "The New Jersey Supreme Court found that expert testimony on shaken baby syndrome in “no-impact” cases does not meet scientific reliability standards. The Court emphasized that such testimony is not generally accepted in the scientific community. The ruling underscores the importance of robust evidence and appropriate resources in handling these complex cases.
GIST: "Although Daubert remains the predominant test for the admissibility of expert opinions, a number of jurisdictions retain Frye and its general acceptance threshold as the standard. But the two strands—reliability and general acceptance—were intertwined in a late 2025 decision of the New Jersey Supreme Court addressing the admissibility of “shaken baby syndrome [SBS]” testimony in a “no-impact” case, one where the baby is shaken, but there is no banging of the child’s body against a wall, floor, crib, or similar hard object.
The case is State v. Nieves, 345 A.3d 1127 (N.J. 2025). And the New Jersey Court ruled on the claim of Mr. Nieves and another defendant as to whether the lower-court exclusion of expert testimony that shaking an infant, without more, could cause brain injuries. To determine whether to affirm the exclusion, the court detailed the history of SBS and the scientific challenges to the same and then reviewed how New Jersey’s Frye test incorporates “reliability.”
For anyone who litigates, defends, or judges in criminal prosecutions, Nieves is a must-read first because it details the genesis of SBS. That historical exegesis is also essential reading for anyone interested in science, “fit for the forum,” i.e., forensic science. Read carefully, it is a tale of unjustified extrapolation from a handful of studies—not all of which involved infants—to a conclusion among certain members of the medical community that this was solid science. This is reflected in the language the court uses to trace that history:
In the years following Dr. Caffey’s 1974 study, the theory of whiplash infant shaking syndrome, later referred to as shaken baby syndrome, began to gain traction in the medical community. That acceptance was based almost entirely on Dr. Guthkelch and Dr. Caffey’s case studies, both of which relied on Dr. Ommaya’s scientific study as the sole source of experimental scientific data behind the theory, notwithstanding the fact that Dr. Ommaya’s study had nothing to do with the shaking of infants.
345 A.3d at 1137 (emphasis added). The court emphasized that “Dr. Caffey did not conduct any biomechanical experiments of his own in support of that study and relied on the review of cases from other studies. …” Id. at 1135. Elsewhere, the court referenced the reliance on “purported direct evidence” that the researchers themselves admitted was “meager.” Id. at 1136.
What clearly impressed the court was the contrary research, that based on biomechanical studies. Also important were the analyses by researchers relied on by the supporters of SBS that called its hypothesis and research into question.
Regarding the biomechanics of retinal hemorrhages, Dr. Ommaya opined that “the levels of force required for retinal bleeding by shaking to damage the eye directly is biomechanically improbable,” given that small masses like the eye require levels of force even higher than larger masses like the brain.
Significantly, Dr. Ommaya critiqued the assumptions upon which theories about mechanisms of pediatric retinal and brain injuries in literature have been based. … Dr. Ommaya stated that “[t]hese assumptions individually and in concert are ambiguous or incorrect” even though those very assumptions had been used as the bases for the differential diagnoses of SBS, “usually without reference to available biomechanical analysis.”
A decade after Dr. Ommaya signaled that SBS lacked an underlying scientific foundation, Dr. Guthkelch, whose study relied on Dr. Ommaya’s whiplash experiment and was in turn cited by Dr. Caffey, also questioned the science behind SBS.
Id. at 1139. Put simply, the court seemed to weigh hard science against more conjectural approaches and found the latter to be wanting.
Beyond a lesson in how to weigh competing forensic claims, Nieves had to fit it into an evidence-law framework. Although New Jersy has shifted to a Daubert-like standard for expert evidence in criminal cases, the court returned to Frye because that is the legal regime Mr. Nieves’s case was tried under.
New Jersey’s framework, even under Frye, mandated a reliability determination. “Notwithstanding the Frye test’s emphasis on general acceptance in the relevant field(s), the science underlying the expertise must have a sufficient scientific basis to produce uniform and reasonably reliable results. …” Id. at 1160 (internal quotations and citations omitted).
The court set the reliability threshold as a high one, explaining that “[g]eneral acceptance entails the strict application of the scientific method, which requires an extraordinarily high level of proof based on prolonged, controlled, consistent, and validated experience.” Id. at 1161.
What proved critical to its ruling was then defining the relevant “community,” or here “communities.” Finding the roots of SBS theory in the work of biomechanical research, the court determined that “the relevant scientific communities for purposes of determining the reliability of SBS/AHT expert testimony are both the medical/pediatric community and the biomechanical engineering community.” Id. at 1366. Because the latter did not “generally” accept SBS in no-impact cases, Frye was not satisfied. [The court also reminded us that general acceptance is not forever—as science changes, so can the level of acceptance.]
On the reliability prong, the court found that independent of the acceptance determination, the research simply did not support the claim, doing so in an incisive review of decades of study:
[T]here was no test supporting a finding that humans can produce the physical force necessary to cause the symptoms associated with SBS/AHT in a child. The trial court further found SBS/AHT to be a theory not anchored in facts developed through reliable, scientific testing to confirm the diagnosis. This Court acknowledges that humans cannot be used as test subjects in potentially dangerous experiments regarding SBS/AHT, so there may never be a perfect scientific test. It is true that there are limitations to researching and understanding SBS/AHT and the forces necessary to result in the injuries associated with the diagnosis. But those limitations should not give way to assumptions in making an SBS/AHT diagnosis for which significant criminal liability follows when no other evidence of abuse is present.
Id. at 1168.
New Jersey did not shut the door on SBS testimony in no-impact cases in the future if the science developed and could establish the reliability of its premises. But that day is not yet here. Nieves stands as a comprehensive assessment of SBS; as a cautionary tale of the dangers of extrapolating cause from inadequate or inapposite studies; and as a reminder of the importance of rigorous application of the standards for admitting expert proof, evidence that has special impact because of the witness’s “singular status in the courtroom … as having been deemed, by the court, sufficiently knowledgeable to offer testimony beyond the specifics of a particular case.” Id. at 1132 (internal quotations and citation omitted). In other words, jurors see the expert as approved by the court, so it is that institution’s responsibility to police such testimony.
There is one final note. The reason the court could issue such a comprehensive opinion was because the litigants included the statewide office of the New Jersey Public Defender. That office ensured that the litigation was well-resourced with an abundance of top-caliber experts. In a nation where indigent defense is often underfunded and where court-appointed and many retained lawyers lack the time and finances to put such a case together, Nieves is a poignant reminder that if the accuracy of science is going to be tested in the context of a criminal case, to get it right there is a need for expertise and money—and if courts confront such claims without those two essentials, they should pause and bring in amici or ensure funding before making decisions that can have long-lasting consequences."
The entire story can be read at:
https://www.americanbar.org/groups/criminal_justice/resources/magazine/2026-fall/general-acceptance-reliability-disagreement-shaken-baby-evidence/?shem=aimgspe,
PUBLISHER'S NOTE: I am monitoring this case/issue/resource. Keep your eye on the Charles Smith Blog for reports on developments. The Toronto Star, my previous employer for more than twenty incredible years, has put considerable effort into exposing the harm caused by Dr. Charles Smith and his protectors - and into pushing for reform of Ontario's forensic pediatric pathology system. Please send any comments or information on other cases and issues of interest to the readers of this blog to: hlevy15@gmail.com. Harold Levy: Publisher: The Charles Smith Blog. FINAL WORD: (Applicable to all of our wrongful conviction cases): "Whenever there is a wrongful conviction, it exposes errors in our criminal legal system, and we hope that this case — and lessons from it — can prevent future injustices."Lawyer Radha Natarajan: Executive Director: New England Innocence Project; FINAL, FINAL WORD: "Since its inception, the Innocence Project has pushed the criminal legal system to confront and correct the laws and policies that cause and contribute to wrongful convictions. They never shied away from the hard cases — the ones involving eyewitness identifications, confessions, and bite marks. Instead, in the course of presenting scientific evidence of innocence, they've exposed the unreliability of evidence that was, for centuries, deemed untouchable." So true
