Leo Ackley (left) and Anthony Ball are charged with felony murder and first-degree child abuse in the deaths of two toddlers. (Calhoun County Sheriff's Office)

The contentious debate over Shaken Baby Syndrome has moved to the courtroom in Michigan, where two men accused of killing toddlers are questioning the reliability of the diagnosis.

Leo Ackley and Anthony Ball are separately charged with felony murder and first-degree child abuse for the deaths of their girlfriends' daughters. Attorneys for the men have teamed up to try to prove that the murder cases against Ackley and Ball are the results of overzealous prosecution based on the flawed science of Shaken Baby Syndrome.

Prosecutors, however, say the defense teams are glossing over years of scientific research supporting the validity of Shaken Baby Syndrome.

Attorneys for the two men said medical experts have relied on three injuries to reach the conclusion that both victims were violently shaken: bleeding behind the eyes, bleeding on the surface of the brain, and brain swelling. Those injuries alone, defense attorneys said, are not sufficient to prove that the toddlers were abused.

"Nobody is absolutely and medically certain or scientifically certain what produces that triad of injuries and what type of force is necessary to produce those injuries," Ball's attorney, Kimberly Schroder, told The Washington Post. "The triad alone is not sufficient."

The defense attorneys also believe that there are alternate explanations to the children's deaths.

In Ball's case, Schroder said the child was involved in a car accident a few days before she died.

In Ackley's case, an expert witness will testify that the child's injury was old and that she was nauseous a week before she was found unresponsive, attorney Andrew Rodenhouse said. What caused the injury, Rodenhouse said, is unknown.

Ackley and Ball had asked the Michigan Supreme Court to halt their trials and hear their cases. But the justices on Wednesday denied the request, saying they were not persuaded that they should hear the issues presented.

Ackley was convicted and sentenced to prison in 2012 for the death of 2-year-old Baylee Stenman. The Michigan Supreme Court overturned his convictions and ordered a new trial last year because his former defense attorney failed to provide witnesses to challenge the testimonies of the prosecution's experts. His second trial began this week in Calhoun County, Mich.

Ball was charged in 2014 in the death of his fiancee's 20-month-old daughter, Athena Ramey. His trial is scheduled to start next week in the same courtroom as Ackley's trial.

Calhoun County Assistant Prosecuting Attorney Karen Pawloski argued in court records that the focus on Shaken Baby Syndrome "is of questionable relevance" and misleading.

"This is not a Shaken Baby Syndrome case," Calhoun County Prosecutor David Gilbert told The Post. "It implies that if you shake a baby hard enough, injuries occur. That's not the argument in this case. We're not claiming that the baby was shaken. We're claiming the baby was injured." Gilbert said that both children suffered traumatic brain injury as a result of abuse.

In court records, prosecutors used the term "abusive head trauma," which has been used interchangeably in the medical community with Shaken Baby Syndrome.

Schroder, the defense attorney, said the terminology doesn't matter much. "The bottom line is not so much the term; it's the triad of injuries that when medical professionals and prosecutors see those, they have a knee-jerk reaction and presume it's homicide," she said.

The arguments brewing in the Michigan courtroom reflect the debate that has divided the medical community: Over the past decade, a number of doctors have questioned the science behind Shaken Baby Syndrome. Since 2001, there have been nearly 2,000 cases in the United States involving children who were violently shaken, according to "Shaken Science," a 2015 Washington Post series. In 213 of those cases, charges were either dropped or dismissed, or the convictions were overturned after doctors found that the children originally said to have been killed or injured by Shaken Baby Syndrome were misdiagnosed.

The American Academy of Pediatrics called The Post's investigation a "disturbing" and "seriously unbalanced" report that sowed doubt about well-established scientific issues. Physicians Howard Dubowitz and Errol Alden argue that those who dispute Shaken Baby Syndrome are a "tiny cadre of physicians" who concoct theories to explain symptoms associated with the syndrome.

The American Academy of Pediatrics recommends that doctors use the term "abusive head trauma" instead of Shaken Baby Syndrome, because shaking alone does not explain the injuries, and most cases likely involve multiple forces.

But David Moran, of the Michigan Innocence Clinic, said even the federal government has started to recognize that the science behind the diagnosis is disputable. The Michigan Innocence Clinic recently received a $250,000 federal grant to challenge convictions based on Shaken Baby Syndrome diagnosis.

Moreover, a September report by the President's Council of Advisors on Science and Technology mentioned in a footnote that questions about the scientific validity of certain types of forensic science, such as arson and Shaken Baby Syndrome, "require urgent attention."

Shaken Baby Syndrome was and still is a hypothesis, not proven science, said Moran of the Michigan Innocence Clinic. "The hypothesis is that if you see these particular signs, you can diagnose that the baby was violently shaken," Moran said. "But there are cases where babies have been observed falling, accidents at home, short falls at the playground, that produce these exact same injuries."

What's needed now, Moran said, is an impartial scientific body that will review the literature on Shaken Baby Syndrome and determine whether the hypothesis is correct.

A. Norman Guthkelch, a British pediatric neurosurgeon who had a key role in the Shaken Baby Syndrome hypothesis, also has said that the science is faulty and there should be an independent review of Shaken Baby convictions.

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