The Imperfect Science Of Justice

Balko brings us the latest on Shaken Baby Syndrome:

New research suggests that most humans aren’t capable of shaking an infant hard enough to produce the symptoms in SBS. It usually takes an accompanying blow to the head. And in about half to two-thirds of the 200 or so SBS cases prosecuted each year in the U.S., there are no outward signs of physical injury. Indeed, this is the reason SBS is such a convenient diagnosis. It allows prosecutors to charge a suspected abuser despite no outward signs of abuse. But we now know that other causes can produce these symptoms, which means that some percentage of the people convicted in SBS cases are going to prison for murders that may have never happened.

He contrasts this SBS research with DNA testing:

The blood or semen or hair either matches the defendant, or it doesn’t. It will show that either the defendant raped or murdered the victim, or that someone else did. Things get murkier when the question isn’t who committed the crime, but if a crime was committed at all. The new research into SBS doesn’t state definitively that without external injuries, a child couldn’t have died from shaking. It suggests only that there are other possibilities—that shaking wasn’t the only possible cause of death. It isn’t an advance in science that will produce dispositive exonorations. It’s an advance that merely calls prior convictions into question.