By Eryn Brown
On March 30, 1981, 25-year-old John W. Hinckley Jr. shot President Ronald Reagan and three other people. The following year, he went on trial for his crimes.
Defense attorneys argued that Hinckley was insane, and they pointed to a trove of evidence to back their claim. Their client had a history of behavioral problems. He was obsessed with the actress Jodie Foster, and devised a plan to assassinate a president to impress her. He hounded Jimmy Carter. Then he targeted Reagan.
In a controversial courtroom twist, Hinckley’s defense team also introduced scientific evidence: a computerized axial tomography (CAT) scan that suggested their client had a “shrunken,” or atrophied, brain. Initially, the judge didn’t want to allow it. The scan didn’t prove that Hinckley had schizophrenia, experts said — but this sort of brain atrophy was more common among schizophrenics than among the general population.
It helped convince the jury to find Hinckley not responsible by reason of insanity.
Nearly 40 years later, the neuroscience that influenced Hinckley’s trial has advanced by leaps and bounds — particularly because of improvements in magnetic resonance imaging (MRI) and the invention of functional magnetic resonance imaging (fMRI), which lets scientists look at blood flows and oxygenation in the brain without hurting it. Today neuroscientists can see what happens in the brain when a subject recognizes a loved one, experiences failure, or feels pain.
Despite this explosion in neuroscience knowledge, and notwithstanding Hinckley’s successful defense, “neurolaw” hasn’t had a tremendous impact on the courts — yet. But it is coming. Attorneys working civil cases introduce brain imaging ever more routinely to argue that a client has or has not been injured. Criminal attorneys, too, sometimes argue that a brain condition mitigates a client’s responsibility. Lawyers and judges are participating in continuing education programs to learn about brain anatomy and what MRIs and EEGs and all those other brain tests actually show.
Most of these lawyers and judges want to know such things as whether brain imaging could establish a defendant’s mental age, supply more dependable lie-detection tests or reveal conclusively when someone is experiencing pain and when they are malingering (which would help resolve personal injury cases). Neuroscience researchers aren’t there yet, but they are working hard to unearth correlations that might help — looking to see which parts of the brain engage in a host of situations.
Progress has been incremental but steady. Though neuroscience in the courts remains rare, “we’re seeing way more of it in the courts than we used to,” says Judge Morris B. Hoffman, of Colorado’s 2nd Judicial District Court. “And I think that’s going to continue.”
Picture: Cstpierre [Public domain], https://commons.wikimedia.org/wiki/File:Trialcourtroom.JPG