Experts offer multiple explanations for infant's death
by Dee J. Hall
May 19, 2014
Medical experts reviewing evidence in the 2007 death of 4-month-old Lincoln Wilber disagree about what may have caused the infant to become unresponsive while in the care of his provider, Jennifer Hancock of Verona.
Four experts — including nationally known doctors who specialize in so-called shaken baby syndrome, also known as abusive head trauma — testified in Hancock’s 2009 trial that Lincoln died of abuse and Hancock was the only logical suspect.
But new theories ranging from a heart virus to sudden infant death syndrome (SIDS) to a blood clot have emerged.
In interviews with students reporting for The Medill Justice Project at Northwestern University, medical experts, including prominent forensic pathologists and abusive head trauma authorities, raised questions about the cause of Lincoln’s death — and whether it could be tied to the 5½ hours he spent in Hancock’s care.
Even though Lincoln had no neck injury or external sign of abuse, several prosecution experts testified he was killed by someone who inflicted trauma to his head, causing the veins in his brain to rupture. They cited a suspicious fracture of his left leg and what appeared to be a fractured skull.
Most of the witnesses said that whoever harmed Lincoln must have done so just before he lost consciousness at Hancock’s home on Sept. 7, 2007. Hancock was charged and convicted in Dane County Circuit Court in 2009 with killing Lincoln. She is serving a 13-year sentence at Taycheedah Correctional Institution in Fond du Lac.
But the medical community is split on whether the types of injuries seen in Lincoln are always caused by shaking, trauma to the head or even abuse.
Shaken baby syndrome as a cause of death has come under increasing scrutiny as some doctors have identified natural or accidental causes of death for infants with brain injury who die with no external signs of harm. Around the time Hancock was charged, prosecutors began referring to abusive head trauma as a cause of death in part to avoid growing questions over the validity of shaken baby syndrome.
Some experts, including Dr. George R. Nichols II, are skeptical. He likened the belief that children can be killed with no external trauma to a “religion” that leads some doctors to ignore medical information casting doubt on shaken baby syndrome or abusive head trauma as a cause of death.
“When it becomes a religion, a belief system,” Nichols said, “it’s tough to overcome.”
Nichols served 20 years as Kentucky’s chief medical examiner until 1997, during which he testified against defendants in shaken baby cases.
Nichols had been picked to testify for the defense in the case against Hancock but ultimately did not, citing the boy’s leg fracture as possible evidence that someone had abused Lincoln.
But at the request of The Medill Justice Project, he reviewed the medical images used at trial. Nichols concluded that the injuries to the boy could have occurred shortly before or after Lincoln was rushed to the hospital. But he said it was difficult to say exactly when those injuries occurred.
Jurors don’t like to hear, “I don’t know,” Nichols said, but sometimes that’s the only appropriate answer.
Questions on cause, timing
Dr. Michael Stier, the forensic pathologist who conducted the autopsy of Lincoln Wilber and testified for the prosecution, also raised questions about the timing of the injuries.
“The science here is not as accurate as some would believe it to be,” he said.
Stier said he’s no longer certain that the infant was abused. He said he can no longer rule out a heart virus that he found in Lincoln. And Stier has a new theory: Lincoln may have died of the type of unexplained infant death commonly called SIDS.
The State Journal was unable to question the prosecution’s expert witnesses in the Hancock case to see if the new theories about Lincoln’s death would have affected their testimony. Repeated emails left with two of the prosecution’s four expert witnesses were not returned. Two others declined to comment.
Dane County Assistant District Attorney Thomas Fallon also declined comment, citing ethical obligations not to engage in pretrial publicity in the case, which is being appealed.
Fallon is on the international advisory board for the National Center on Shaken Baby Syndrome, which says more than 300 babies die in the U.S. each year from shaking.
The group’s spokesman, Ryan L. Steinbeigle, issued a strongly worded statement to the State Journal. He insisted there was no disagreement in the mainstream medical community about shaken baby syndrome or abusive head trauma and that questions about the diagnosis are being drummed up by “a handful of experts who frequently testify for the defense.”
“The American Academy of Pediatrics, Centers for Disease Control and Prevention, National Association of Medical Examiners, American Academy of Ophthalmology all recognize (abusive head trauma/shaken baby syndrome) as a form of infant abuse,” he said, adding that the diagnosis of abusive head trauma “is supported by at least 700 peer-reviewed, clinical medical articles.”
“While the idea of a flawed diagnosis putting innocent people behind bars may be effective in selling newspapers ... it is not based on any real science or evidence and actually does more harm by misleading the public to believe that shaking a baby is a safe care-giving behavior,” he said.
Experts: Several possible causes of death
Among the experts reviewing evidence in the Hancock case for The Medill Justice Project was Dr. Julie Mack, a radiologist in Hershey, Pa., who has testified for the defense in such cases.
After viewing Lincoln’s MRIs and CT scans for this article, Mack said she believes Lincoln’s brain bleeding began at least 24 hours before he was under Hancock’s care.
Mack said she also detected a small clot that could have been cortical venous thrombosis, an uncommon blood clot within a vein in the head.
And she raised questions about the timing of Lincoln’s leg fracture. Doctors made multiple attempts before inserting an intravenous needle into Lincoln’s left leg after he was brought to American Family Children’s Hospital. They told investigators that nothing they did would have caused the fracture.
But Mack contended that, “If there was a fracture, it didn’t happen when the child had a heartbeat.” She believes there would have been inflammation and more bleeding at the site of the fracture if there were a heartbeat.
Dr. Brian Forbes is an ophthalmologist at The Children’s Hospital of Philadelphia who has examined retinal damage in abused children. He has testified against people charged in shaken baby syndrome cases. Forbes declined to discuss Lincoln’s case but said, “kids seldom just die out of the blue.”
He acknowledged, however, that it’s often difficult to tell when injuries are inflicted. That was a key question in the Hancock case.
“The timeline is very, very difficult to elucidate,” he said, referring to such cases generally.
Old brain injury to blame?
Medical records raise other questions. Lincoln’s heart contained a dormant virus. And he was born prematurely by emergency cesarean section.
Defense expert Dr. Ronald Uscinski, a neurosurgeon who teaches at Georgetown University and The George Washington University, testified in Hancock’s trial that the cesarean caused an initial brain bleed — called a subdural hematoma — and made Lincoln susceptible to rebleeds.
Hancock testified that the day Lincoln became unresponsive, she found a 3-year-old girl weighing nearly 40 pounds lifting herself off Lincoln after apparently falling on him.
Uscinski, who often testifies on behalf of defendants, speculated that the weight of the toddler falling on Lincoln would cause enough impact to cause rebleeding in his brain.
“I stand by what I said,” Uscinski said in an interview. “I am sure, in my opinion, that this baby had a chronic subdural hematoma that most likely stemmed from birth.”
Forensic neuropathologist Dr. Jan Leestma said in an interview that 20 percent to 30 percent of births result in some kind of trauma, and a small percentage of those birth traumas could result in a subdural hematoma that might take a month or two to show up.
Leestma said placental abruption, as happened prior to Lincoln’s birth, is the kind of event that could indicate birth trauma.
Leestma, who has a private practice in Chicago and has testified for the defense in such cases, said an infant’s body deals with the added pressure of a chronic subdural hematoma by reabsorbing some of its cerebrospinal fluid into the blood. That leads to a wax-and-wane effect, where an infant will appear to get sick and seemingly get better before falling ill again.
Nine days before Lincoln went unresponsive, his parents took him to the hospital because he was projectile vomiting, acting fussy and had a noticeably decreased appetite. Doctors diagnosed and treated Lincoln for gastro-esophageal reflux, but Leestma said this could have been a symptom of a chronic brain injury.
Leestma added that many infants with such conditions “don’t like to lie supine — and calm down when held or put to sleep in a bouncy chair or something more vertical (because) intracranial pressure may rise when lying flat, and falls when vertical.”
Hancock and Lincoln’s parents, Erin and Benjy Wilber, all told investigators that the 4-month-old preferred to be upright and would often cry when laid down.
Possible blood clot?
Another theory comes from Dr. Michael Laposata, the head pathologist at Vanderbilt University Hospital in Nashville, Tennessee, and an expert in blood clotting.
Laposata has written about the misdiagnosis of abuse in infants with bleeding disorders. He said in an interview that because Lincoln’s mother had Lupus and a history of blood clots, there is a high likelihood that Lincoln had similar problems.
If Lincoln had a clot, it could have led to increased blood pressure, rupturing blood vessels and creating the subdural hematoma, Laposata said.
The possibility of a blood clot due to these genes would only be amplified by an infection, Laposata said. The autopsy found viral particles in Lincoln’s heart, potential evidence of a condition or infection.
In his report, Stier, the forensic pathologist who performed the autopsy, said the particles were not a cause of death. He also found no clot in Lincoln’s brain or elsewhere in his body.
But in an interview, Stier said he can no longer rule out involvement of the heart virus in Lincoln’s death. And Laposata said if there were a clot, Stier may not have been able to detect it.
Carrie Sperling, co-director of the Wisconsin Innocence Project, is preparing an appeal of Hancock’s case. She said the myriad theories of Lincoln’s cause of death and advances in medical understanding about head injuries “confirms everything we (innocence attorneys) know about these kinds of cases and why they should be reviewed.”