
The Shaky Science of Shaken Baby Syndrome
Prosecuters have charged parents and caretakers with shaking
infants to death. But how valid is that diagnosis, and how reliable is
the evidence behind it?
By Maia Szalavitz | @maiasz | January 17, 2012
On New York’s Rikers Island, the parents of baby Annie await trial for
shaking their infant girl to death. Her mother and father deny harming
their child in any way, but prosecutors claim the 70 day old baby died
with a severely fractured skull and brain damage consistent with being
shaken violently.
Shaken baby syndrome presents a terrifying dilemma to the criminal
justice system: a false conviction leaves a grieving parent or other
innocent in prison for years while an undeserved exoneration could
allow a dangerous child abuser to kill again. Unfortunately, the
medical science used to determine the cause of death in infants
suspected of being shaken to death is far from precise, and certainly
not conducive to the simple “guilty” or “not guilty” decisions that
courts require.
In a highly contested case heard by the Supreme Court last fall, the
original guilty verdict against grandmother Shirley Ree Smith for
having shaken her grandson to death was overturned by the Ninth Circuit
Court of Appeals, which said there was “no physical evidence” and “no
demonstrable support” for the conviction. Ree Smith had been visiting
her grandchildren and had no prior history of abuse.
Shaken baby Syndrome (SBS) is typically diagnosed by a “triad” of
symptoms: bleeding in the retinas of the eyes, bleeding under the dural
matter of the brain (subdural hematoma) and brain swelling— all
occurring in the absence of a recent car accident or other clear
explanation for the injuries. In Smith’s case, her seven-week old
grandson had no retinal bleeding at all. Although he did have a
subdural hematoma, his brain was not swollen: he didn’t even meet two
of the three triad criteria. Moreover, most cases of SBS occur among
highly isolated new parents or caregivers who are overwhelmed by the
baby’s incessant crying. But Smith was a grandmother with no history of
abuse who spent the the night in her grandson’s room along with two
other children— and no one even heard the baby cry after he went to bed.
The Supreme Court did not address Smith’s innocence but upheld her
conviction on procedural grounds, saying that the Appeals Court had
overstepped its bounds by overruling the jury’s view of the evidence.
The ruling leaves open the question of whether Smith did or did not
cause any harm to her grandson, and consequently, Smith, who had been
released, may have to return to prison even though her conviction rests
on what her attorneys are arguing is unsound scientific evidence.
In the current case, reported by the The New York Times, the suspects
are still awaiting trial. Chinese immigrants Li Hangbin and Li Ying
became parents of a baby girl they named Annie in August 2007. In
October of that year, they were charged with violently murdering her:
the father accused of brutally shaking the two month old and the mother
of failing to call 911 immediately afterwards. Prosecutors have painted
a picture of harsh, uncaring parents who were so unconcerned about
their baby that they waited hours after she was clearly severely
injured to call for help. They claim that Annie had a massive skull
fracture from two non-accidental blows to the head, hemorrhaging in the
brain, two broken legs and a fractured rib.
But activists in the Chinese community have discovered that the Li’s
may have a family history of osteogenesis imperfecta, a disease that
can cause bones to break easily, which has previously been mistaken for
shaken baby syndrome in some infant deaths. The Li’s supporters say
that six family members died prematurely of the disorder, two of them
at age two months, as in Annie’s case.
Both cases highlight why incidents involving alleged shaken baby
syndrome are so challenging for the courts. Any time a loved one’s care
of an infant is questioned, emotions run high — and the courts, by
definition, are forced to put aside passions in favor of evidence that
only tells half the story. Physical evidence is only the end result, or
the final outcome of what may have been a criminal act, but the cause
behind that evidence isn’t always obvious. Parents may not be aware
that their child is vulnerable to fractures, and child abusers don’t
typically admit what they have done. The final outcome of a harmed
child however, may look the same. For scientists studying shaken baby
syndrome to better glean patterns of symptoms more typical of innocence
or guilt, this raises the level of uncertainty to a degree that many
would be uncomfortable calling “reasonable doubt.”
Take, for example, the diagnosis of SBS itself. SBS, fortunately,
affects only a small number of babies— around 1,200 to 1,400 annually.
In at least 30% of cases, the diagnosis is relatively clear, because
there is prior evidence of abuse. But for the remaining majority of
cases, the cause is far more confusing, partly because other possible
explanations are equally controversial and ambiguous, making their
study more difficult. First is SIDS, or sudden infant death syndrome,
which is the leading cause of death of babies aged one month to one
year, claiming 2000 to 3000 babies annually in the U.S. No one knows
what causes it, which makes diagnosis challenging, although some deaths
may be due to accidental smothering from bedding either in a crib or
when a child sleeps in its parents’ bed.
Second, there are numerous rare genetic disorders—like osteogenesis
imperfecta— that can kill infants in ways that can lead to a mistaken
SBS diagnosis. Osteogenesis imperfecta affects just 1 in 20,000 births;
there are thousands of similarly rare disorders that can cause infant
death, many of which have not been studied significantly.
Finally, there’s the curious case of Munchausen Disease by Proxy (MPB),
a psychiatric disorder in which mothers deliberately injure and
sometimes kill their children in a quest for medical attention and
praise for their devoted “caring” for injured or sick kids. While the
cause of death in both SBS and in murdered children of parents with MPB
is abuse, the dangerousness of the Munchausen parent who deliberately
produces injury is far greater than that seen in typical SBS. In SBS,
momentary anger and frustration typically produces an overreaction and
injury— but there is generally no consistent intent to inflict severe
or fatal harm as in MBP.
As a result, because SBS is basically a diagnosis of exclusion and
involves ruling out rare diseases that physicians may have never even
seen, reasonable doubt may be unavoidable. And that’s especially true
in the 50-75% of cases where the triad of head injuries is the only
evidence of SBS.
To address the confusion, experts are attempting to clarify criteria
that distinguish SBS from these other conditions. Previously, for
example, doctors believed that shaking alone—without banging the
child’s head against something— was a common cause of SBS death. Now
most think that impact is usually needed for serious injury or death.
In 2009, the American Academy of Pediatrics decided that the condition
should be called “abusive head trauma” to reflect the new understanding
of the condition.
But that doesn’t mean that diagnosing SBS will necessarily get easier.
One recent study of babies and fetuses who died from birth injuries or
disease (and could not have been shaken because they never left the
hospital) found that many had subdural hematomas, or bleeding in the
brain, that could later have been mistaken for signs of abuse if they’d
lived. Other studies find that babies can be injured by abusive head
trauma but remain lucid for hours or possibly days before collapsing—
meaning that the time frame of the crime may be expanded, which in turn
widens the pool of suspects based on their contact with the victim.
Given all this, it seems unjust to sentence people—most of whom have
suffered the most grievous loss a parent can face— to years of prison
in cases where the “triad” is the only evidence that the baby died from
abuse. Perhaps in cases where abuse is suspected but cannot be proven,
suspects might be monitored by child welfare authorities or precluded
from working with children. But when the science is this shaky, it
isn’t yet ready for the courtroom, where lives hang in the balance. In
the Li’s case, that includes not only their own but that of their other
daughter— named Nianni, or “remember Annie” in Chinese— who was born
while her mother was in shackles and knows her only from jail visits.
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