By Emily M. Gause and Fernanda Torres
(As published in Washington Criminal Defense Magazine, February 2016)
This article provides a broad outline of what practitioners defending child abuse cases involving closed head injuries need to know regarding “Abusive Head Trauma” (AHT) (formerly known as shaken baby syndrome), including problems with the AHT diagnosis, investigation requirements, and available resources.
Each case is unique, of course, but an AHT case will likely follow a pattern. A child in acute distress, or worse, is rushed to the hospital by a caregiver. CT scans indicate subdural bleeding; possibly, ophthalmologic exams indicate profuse retinal bleeding in one or both eyes; other injuries may or may not be noted. Brain injury may be present. If the history reported by the caregiver(s) is considered to be inconsistent with the medical findings, it is said that child abuse needs to be “ruled out.” A child abuse expert is called in to consult. That person reviews the child’s hospital records, including the reported history. Blood tests are done and certain conditions may be excluded based on the results or follow-up testing. If applicable, autopsy results are considered. Abusive head trauma is diagnosed through the “differential diagnosis” method that supposedly rules out other explanations. According to the child abuse expert, whiplash forces, possibly with impact, explain the “constellation of injuries” of subdural hemorrhage and/or retinal hemorrhage and/or brain damage and/or other injuries. The last caregiver, or the last person to be left alone with the child, will be said to be responsible. This person, now a suspect, is questioned by doctors, police, DSHS, or all of the above. The suspect and family members are likely told that it was medically determined that abuse is the only explanation for the observed injuries. Possibly, a “confession” happens. The confession is said to corroborate the diagnosis.
When reviewing the case, it is important to know you cannot assume that: 1) The medical findings reflect recent, or acute, events; 2) the medical findings are the result of injury and not a disease process; 3) the child abuse expert reviewed all relevant records, including all of the child’s medical history; 4) the reported history is, in fact, inconsistent with the medical findings; 5) the differential diagnosis process really ruled out all alternative explanations; 6) the medical examiner’s findings, if applicable, support an abuse diagnosis; 7) the child’s onset of symptoms was immediate; 8) the suspect’s alleged confession describes truly abusive actions, and; 9) the AHT determination rests on well-supported medical science. Given the state of the science, explored below, the only reasonable conclusion warranted by the medical facts may be that abuse is only one of many possible explanations, or that the cause of the medical findings (or death) is unknown.
A. The History of AHT
In 1968, Dr. Ayub Ommaya, a biomechanical engineer, conducted a study whereby rhesus monkeys were strapped into sled-like chairs that traveled over a 20-foot long track and impacted into a wall.[1] Many of the monkeys were found to have subdural bleeding (or bleeding inside the cranium, below one of the meningeal layers surrounding the brain called the dura mater).[2] From this sole study, two British doctors, Drs. Guthkelch and Caffey, hypothesized that shaking could account for intracranial injury in infants with no external evidence of cranial trauma.[3] No further research tested this hypothesis, but it lingered and eventually evolved into what we know as “Shaken Baby Syndrome” (SBS).[4]
Since much has been written about the evolution of SBS in multiple articles that are must-reads for defense attorneys, the background is not explored at length here.[5] The short version is that the shaking hypothesis was adopted by the medical community as the basis of a firm diagnosis of abuse that eventually came to look like this: Subdural bleeding and/or retinal bleeding and/or brain injury in a child is a “constellation of injuries” suspicious for abuse; in the absence of known trauma (such as a car accident) these medical findings are markers that the child was violently shaken. In other words, these findings—also known as the “triad”—are traumatic in origin and, where no history of trauma is reported, are highly specific for abusive shaking.
SBS is now better known as “Abusive Head Trauma” (AHT), a “less mechanistic” term adopted in 2009 by the American Academy of Pediatrics (AAP),[6] largely in response to research raising questions about shaking as a causal mechanism. AHT, like its predecessor SBS, is a medical diagnosis of abuse. Unlike most medical diagnoses, AHT has no set diagnostic criteria and is used to describe any inflicted head injury that is the consequence of violent shaking, blunt impact, or both.[7] The only firm criterion is that the medical findings are the result of abuse.[8]In addition to one or more of the “triad” findings, skull, rib, or long bone fractures, and signs of external trauma (scalp bruising, for example) may or may not be present.
Despite the name change, the idea that shaking alone can cause intracranial injury is still endorsed by the medical community.[9],[10] Thus, simply because State experts diagnose AHT and claim not to know the exact mechanism of abuse does not mean they are not, in essence, talking about SBS. If described as abuse involving a whiplash force or an acceleration/deceleration injury, the conclusion still rests on the underpinnings of SBS. Here, we focus on those cases where the State claims other causes[11] have been “ruled out” and it is a whiplash force—possibly with impact—that caused the abusive head injury, and where there are no other injuries indicating abuse.[12] We refer to AHT as the SBS/AHT hypothesis.
B. The biomechanics of SBS/AHT
According to SBS/AHT hypothesis, when a child’s head moves back and forth in an arc during violent shaking, rotational forces on the brain cause bridging vein rupture and, in the case of retinal hemorrhaging, vitreoretinal traction.[13] Secondarily, increased intracranial pressure and oxygen deprivation can cause brain swelling and damage.[14] Two questions flow naturally from the SBS/AHT proposition: 1) Should we expect to see neck injury? 2) How severe does the shaking have to be? Biomechanical research has tried to answer both.
On the question of neck injury, Dr. Faris Bandak published research in 2005 finding that infants subjected to the levels of rotational velocity and acceleration called for in the SBS literature would experience forces on the infant neck far exceeding the limits for structural failure of the cervical spine.[15] In other words, neck injury has to occur before head injury.
Regarding the force necessary to inflict injury, multiple biomechanical studies have looked at the effect of shaking on infants and children by measuring the angular acceleration forces of shaking. The results are consistent that the force generated by shaking is well-below injury thresholds.[16] Simply stated, the most vigorous shaking an adult can muster generates relatively little force. The research confirmed that drops of just a few feet produce far more angular acceleration than does the most forceful shaking.[17]
Indeed, the first biomechanical study investigating SBS in 1987 concluded “shaking alone in an otherwise normal baby is unlikely to cause the shaken baby syndrome.” [18] The subsequent studies have reached substantially similar results, even when testing with exaggerated shaking motions, modified dummy necks, or animal surrogates.[19] When one considers that the onlyexperimental basis of the SBS hypothesis—the 1968 Ommaya study—involved energy levels equivalent to vehicle crashes at 30 mph, the results of biomechanical research measuring the effects of shaking are not surprising.[20]
The response to the biomechanical research has been mixed to negative. On the one hand, the name change to AHT reflects doubts about shaking.[21] On the other hand, the AAP still endorses shaking, even without impact, as a plausible mechanism;[22] shaking-only prosecutions continue to be brought;[23] and the biomechanical research is largely ignored or heavily criticized. In the case of the Bandak study, to say that SBS/AHT proponents do not like it would be an understatement. The main criticism is that the findings are the result of numerical error, a point Dr. Bandak has addressed and refuted.[24] The study has not, in fact, ever been shown to be wrong. Yet, State experts will describe it as flawed.
As to the other studies, the response can be fairly summed up as this: The failure of biomechanics to validate shaking as a mechanism of injury is the fault of biomechanics. Supposedly, infant models are not biofidelic, scaling from adult models is not appropriate, and injury thresholds for infants have not yet been established.[25] The infant head is different, the argument goes, and it is not known how infant tissue responds.[26] Along the same lines, State experts like to point out that since we cannot test real babies, biomechanics cannot provide an answer.[27]
The limitations on the science, if true, simply mean we do not know the effects of shaking. In fact, as one court pointed out, the claim that injury thresholds are not yet established “provides a newfound basis for skepticism about causation and mechanism testimony.”[28] And, while we cannot test real babies, this does not mean that if we did test real babies, the results would show shaking causes intracranial injury. These attempts to cast aside the biomechanical research disproving the SBS/AHT hypothesis reveal persistent and pervasive bias.
C. Support in the medical literature
The number of SBS/AHT studies is in the hundreds. As such, State experts can point to
the medical literature for support. The SBS/AHT literature, however, suffers from a major, fundamental flaw: Circularity. This refers to the problem of selecting cases by the presence of the very clinical findings and test results the study seeks to validate.[29] For example, in a circular study looking at retinal hemorrhaging, non-accidental trauma cases are differentiated from accidental trauma cases by the presence of retinal hemorrhaging. Then, when the non-accidental cases have retinal hemorrhaging, it is concluded that retinal hemorrhaging indicates non-accidental trauma. Circular studies assuming what they set out to prove do not have much value, but that has not stopped reliance on such studies. Moreover, at trial, State experts will criticize the literature review first identifying circularity as a major problem.[30]
However, circularity is an acknowledged problem, and efforts to avoid it have resulted in the so-called confessional literature.[31] These are studies where the researchers used perpetrator confessions to supposedly corroborate abuse before classifying a case as abusive.[32] A chapter in an authoritative child abuse textbook edited by Dr. Carole Jenny—a leading child abuse expert and SBS/AHT proponent now based in Seattle—states “the evidence base for shaking isconfessions.”[33] Given the biomechanical research and the circularity problem, this is where the science is today—relying on non-scientific data consisting of imprecise, unconfirmed, alleged confessions, the details of which may not even be known. The multiple, specific issues with the confession studies are discussed at length in the Findley et al. article cited above.[34] It is important to review this discussion, and the underlying studies, so you can educate the fact-finder on the limits of the stated support.
D. Reasonable medical certainty vs. reasonable doubt
At trial, the AHT diagnosis will be stated to a reasonable medical certainty. What
this means may be different for each doctor, and it almost certainly means something far less than beyond a reasonable doubt.[35] If the expert opinion is the only evidence establishing all the elements of the charged offense, as in most AHT cases, a conviction resting upon “reasonable medical certainty” is problematic. To make matters harder, the AHT diagnosis is a bit of a magic trick. The child abuse expert initially relies on medical knowledge purportedly supporting the notion that shaking (with or without impact) causes the medical findings, and this forms the basis of his/her AHT diagnosis. Then, the same expert will claim he/she does not know the exact mechanism of injury. And, voila, the premise (shaking hypothesis) supporting the conclusion (abuse) vanishes, but the conclusion remains. Since the expert is not saying the mechanism of abuse was shaking, this blunts challenges discrediting shaking as mechanism.
The issues are furthered obscured because the term AHT lumps the medical findings, causation and intent together. This makes it difficult to assess causation objectively.[36] Also, the causation determination enjoys the protective cloak of being a medical diagnosis endorsed by the AAP, a fact the State will likely hammer over and over again. Indeed, lending legitimacy to the hypothesis was likely an intended consequence of the name change, given the concern that “[l]egal challenges to the term ‘shaken baby syndrome’ can distract from the more important questions of accountability of the perpetrator and/or the safety of the victim.”[37] Thus, in a legal setting, the AHT terminology helps the prosecution, even as it muddles the issues. Lifting the veil, so to speak, will hopefully help your client.
E. Understanding the medical terms
Providing definitions for the various medical terms involved in an AHT case is outside
the scope of this article. However, there are resources available that will help you with the medical terms that appear in these types of cases.[38] In addition to the terms mentioned above, you should be familiar with the following: Acute, subacute and chronic (and time frames associated with each), gray/white matter differentiation, diffuse axonal damage, hypoxia, ischemia, intracranial pressure, macrocephaly, retinoschisis, subarachnoid hemorrhage.
F. Checklist – Some ideas to consider if you have a case with AHT diagnosis:
1. Read the discovery and look for the common buzzwords – clues that the medical science may be flawed
a. “Constellation of injuries,” “triad”, “shaken baby syndrome” “acceleration/deceleration” “diffuse axonal damage” “rule out diagnosis.”
b. A diagnosis in the first 1-2 hours (knee jerk response diagnosis).
c. Referring to a “confession” as evidence for the medical diagnosis.
2. Develop an understanding of the subject matter so you can adequately defend the case. Read background information about AHT in general. Several resources are cited above. Others are: It Happened to Audrey[39] and “Scenes of a Crime” (documentary about father who falsely confessed to shaking his baby).[40]
3. Research and read decisions: list of cases: Cavazos v. Smith, 132 S.Ct. 2, 8 (2011) (Ginsberg, J., dissenting) (describing the growing doubt about SBS); Del Prete v. Thompson, supra note 25;People v. Thomas, supra note 41; People v. Bailey, 999 N.Y.S.2d 713 (2014) (granting new trial based on newly discovered evidence of SBS); Ex parte Henderson, 384 S.W.3d 833 (new trial granted based on new scientific research on accidental falls); Aleman v. Vill. of Hanover Park, 662 F.3d 897 (7th Cir. 2011) (discussing the agreement that a lucid interval was likely); State v. Edmunds, 308 Wis.2d 374 (2008) (granting new trial based on newly discovered evidence of SBS and discussing alternative causes, lucid intervals, biomechanics, and the shift in medical opinion).
4. Interview client about the child’s history. Interview other spouse or caretaker about medical history. Create a timeline of the child’s life from birth to collapse, including major events (hospitalizations) to minor ones (routine doctor visits). Get family photos at various times showing babies head. Pay special attention to head circumference, as bulging may indicate a chronic hematoma. Gather medical records, including prenatal, birth and pediatrician records. Start this process early and be persistent.
5. Get all medical records from the date of incident, not just what is provided in discovery. Make sure to get MRI and CT scans in original form so you can provide to defense experts later. Don’t dump the medical records on the expert. Organize them per that expert’s specifications.
6. Create executive summary of the case and share with expert. Should include a list of the records you have and do not have, summary of facts in chronological order, abstract of medical records, abstract of child’s medical history.
7. Watch or listen to the interrogation. Note how many times the medical findings or diagnosis was brought during questioning.
8. Obtain expert help. Courts have overturned convictions for ineffective assistance of counsel for the failure to investigate and obtain expert services from a qualified expert.[41] The following is a non-exhaustive list of the types of experts you may need to consult:
a. Radiologist
b. Ophthalmologist
c. Pediatric neurologist
d. Forensic pathologist
e. Epidemiologist
f. Hematologist
g. Biomechanics
9. Develop defense theory. The following is a non-exhaustive list of some potential defenses to the AHT diagnosis:
a. Medical findings were caused by a prior medical issue, not abuse. For example, a rebleed of a subdural hematoma caused in the birth process.
b. Medical findings were caused by an underlying disorder. Examples include: craniocerebal disproportion, developmental disorders, coagulopathy or vascular disease, metabolic or nutritional disorders, infections or post-infectious conditions, hypoxia-ischemia (e.g. airway, respiratory, cardiac, or circulatory compromise), seizures, and recent vaccinations.
c. The medical findings were caused by a short fall.
d. The timing of the injuries cannot be pinpointed to time when defendant was with child; or, injuries were more likely inflicted before by someone else. This is explained by what is referred to as the “lucid interval.” A lucid interval is a period of time between an injury and symptoms in which the baby is acting normal, or close to normal, prior to neurological collapse. But note that what is “normal” for a baby varies and the source of a baby’s fussiness, if any, is hard to identify. There is quite a bit in the medical literature about lucid intervals, and importantly the 2015 AAP clinical report concedes that “[i]nfants with intracranial injuries may have no neurologic symptoms…”.[42]
e. Given the specific facts of the case, the medical conclusion that the child was abused is weakly supported and non-scientific.
f. Present evidence of good parenting. This can be very powerful in AHT cases, as a jury may be wary to convict based on disputed scientific theory. A history of good parenting may decide the outcome.
10. Be prepared to interview State medical witnesses (treating doctors and any child abuse experts):
a. Find and review expert’s testimony in other cases.
b. Consult your defense experts about what questions to ask State doctors.
c. Ask questions about how the doctors engaged in a differential diagnosis? How did they rule out other possibilities? How long did this process take (1 hour? Or days?)?
d. What medical records did they review? Birth records? Pediatrician records? Medical history as provided by mom or dad? A “confession?”
e. How did they determine timing of the injuries?
f. How do they explain the pathology of the injuries? How did they happen? What are they relying on to reach conclusion as to causation?
g. Review literature cited by expert. Does it support conclusion of abuse in this case?
11. Motions/Issues to consider
a. Frye/ER 702/703 – Expert testimony is subject to Frye and the rules of evidence, of course. With the AAP endorsing AHT, it is difficult to argue the diagnosis is not generally accepted and one WA court has determined AHT testimony is admissible.[43]
b. 3.5 Hearing
i. See Adrian Thomas case (and documentary) [44]
ii. Aleman v. Village of Hanover Park (not controlling for WA but still informative)[45]
c. Corpus Deliciti issues – confession alone cannot be basis of charge. Given the weak medical evidence in this area, there may be room to make a motion to dismiss for failure to establish corpus deliciti.
d. Insufficiency of the evidence – Del Prete, Swedish case
e. Motions in Limine to consider in these types of cases:
i. Limit testimony of doctors to the medical findings.
ii. Exclude/limit use of terms SBS and AHT as prejudicial and invading the province of the jury until objective evidence supports an expert opinion on causation (experts may use “consistent with”).
iii. Prevent State from claiming defendant confessed until defendant’s statements are actually before jury.
iv. Limit doctors from testifying as to the opinions or conclusions of third persons, including subordinates of or co-workers with the expert, unless such third person is available for cross-examination on the point. Opinions or conclusions of abuse are not medical findings. ER 702 & 703; State v. Lui, 179 Wn.2d 457 (2014).
v. Limit opinion on ultimate issue—whether the defendant assaulted his child—by using case law that prohibits a witness to opine on the defendant’s guilt. Restrict state doctors from concluding that their diagnosis means that defendant must have assaulted his child.
vi. Limit state doctors testifying outside their area of expertise (for example, ophthalmologists testifying about cranial CT scan findings).
G. Conclusion
AHT cases present unique concerns involving complex medical issues that are the subject of ongoing investigation and debate. We hope this article provided a very basic lesson in the background and current status of the AHT diagnosis and some tools for what to look for if you find yourself with such a case. Both authors are happy to answer questions and provide resources if asked.
Emily M. Gause has been practicing in criminal defense for five years and has her own practice (Gause Law Offices). She focuses on felonies in state and federal courts throughout Washington. She can be reached at emily@emilygauselaw.com.
