Brain Science Enters the Courtroom

Neuroscientist Michael Gazzaniga lectures on law

by Ben Mauk

October 12, 2007

Michael Gazzaniga, a neuroscientist known for bringing hard science into the realm of law and ethics, posed sweeping philosophical questions in a lecture titled “Brains, Minds and Social Process.” Gazzaniga gave the lecture at the Carnegie Institution for Science in Washington, D.C.

“What is the brain for?” asked Gazzaniga, who also directs the Sage Center for the Study of Mind at the University of California, Santa Barbara. “It’s amazing that if you ask this question to an audience of neuroscientists, not many people know the answer.”

He answered his own question: “It’s for making decisions.” But, he added, neuroscientists and philosophers are not settled on whether the brain, a decidedly deterministic system, possesses the volition or “free will” implied by how the legal system treats those who “decide” to commit crimes.

“The brain determines the mind and the brain is a physical entity. … Yet, humans think they are in charge of their actions,” Gazzaniga said. “We feel free, yet brains are automatic.”

“We must revise our notion of social responsibility,” he said.

Gazzaniga went on to discuss diverse issues linked by the brain and the courtroom, such as the validity of pleading not guilty by reason of insanity, the difficulties of diagnosing minimally conscious states and the neuroscience behind behavioral biases that can affect evidence in a trial.

“The issues we want to approach tonight have a large context in the history of law,” he said. And they apply in the present, too, he said later: “There are now 910 cases in the U.S. where neuroscience is an issue.”

Neuroscience and law are familiar subjects for Gazzaniga, who this month was named director of the Law and Neuroscience Project, a newly conceived collaborative effort among more than two dozen universities.

The project, which received a $10 million grant from the The Charles D. and Catherine T. MacArthur Foundation on Oct. 9, seeks “to address the difficult legal questions that will inevitably and quickly arise as neuroscience progresses in its ability to understand and manipulate behavior,” according to the Law and Neuroscience Project’s Web site.

“These are all tough, tough questions,” Gazzaniga admitted near the end of his talk. “We’re nowhere near being ready to answer them all.” However, he recognized the importance of working toward a future “where neuroscientists advise courtrooms on what they know about the brain mechanisms underlying a [court] case.”

The lecture was part of an ongoing series called the Carnegie Institution for Science Capital Science Lectures, which are free and open to the public.

Gazzaniga is a member of the Dana Alliance for Brain Initiatives. His most recent book, The Ethical Brain, was published by Dana Press.