EDGEWATER — In the wake of a crime, there is always one question that tends to linger: why?
In his new book that comes out Feb. 28, "The Brain Defense: Murder in Manhattan and the Dawn of Neuroscience in America's Courtrooms," Edgewater author Kevin Davis explores that question — in particular when it comes to how trauma to the brain impacts behavior.
Davis, a third generation Far North Side journalist, said his natural interest in crime and storytelling helped him accidentally stumble across the subject of neuroscience and criminal acts.
In 1934, his grandfather, a photojournalist for the Chicago Daily Times, shot exclusive photos of John Dillinger while the famous gangster was being flown to Chicago by police.
His fascination with brain injuries began after U.S. Rep. Gabrielle Giffords (D-Ariz.) was shot in the head at a Tucson, Ariz. grocery store in 2011.
Davis said he remembered being curious how the congresswoman would recover.
He began looking into the topic and found a Chicago organization called the Brain Injury Clubhouse, a group whose members included a range of people who had experienced a degree of trauma to the brain.
Davis said he had expected to write a story about how people work through through brain injuries, but he also found some of the subjects had undergone personality changes, with a few even having run-ins with the law.
From there, he "dove right in."
As he continued looking into topic, he frequently came across the 1991 murder case of Herbert Weinstein — a man who became uncharacteristically enraged and strangled his wife to death before throwing her out the 12th story window of their Manhattan apartment.
Weinstein's defense lawyer ordered scans of his client's brain, which discovered a cyst the size of an orange pressing into Weinstein's frontal lobe — where impulse control is located.
Could the growth explain why a normally mild-mannered man would suddenly erupt in a fit of deadly rage?
Davis sought to find out.
"This new area of law neuroscience is kind of opening up some new possibilities for people who may not be legally insane, but certainly have mental health and brain dysfunction that might help explain and diminish their responsibility," he said.
Of course, not everyone who suffers a brain injury commits a crime, Davis points out.
But for those who do, the way neuroscience can potentially help explain or add context to the situation, can mean the difference between life and death for some.
The brain defense is most commonly seen in the sentencing phases of murder trials, when lawyers are allowed to argue for juries to have mercy on the defendant, and that the client's punishment should be lessened because of outside factors such as abuse or trauma.
How neuroscience should be used in court is a huge issue among lawyers and scientists right now.
"That the book really discusses is this battle, I mean there's a real battle out there between lawyers, and a battle between neuroscientists — and a battle among all of them — about the use and misuse of neuroscience in court," Davis said. "And whether it belongs in the legal system at all.
"The bottom line is that neuroscience still doesn't have the answers explaining why exactly somebody does something, so that it's hard to translate to legal cases," he said. "But what it can do is it can help lessen the severity of sentences for people who have committed crimes."
Davis' book follows not just the courtroom drama of the Weinstein case, but researches the blurry line between free will and neuroscience.
Davis will be making two book signing appearances in Chicago: At 6 p.m. Thursday March 2 at Barnes and Noble, 1 E. Jackson Blvd., and 7 p.m. Wednesday March 8 at Book Cellar, 4736 N. Lincoln Ave.