Blame My Genes, Not Me.
A criminal defendant in New Mexico, Anthony Yepez, wants to use neuroscience as a defense to his admittedly criminal act. Yepez didn’t merely wander the streets screaming, nor steal something because of some irresistible impulse to have it. No, Yepez beat a 75‑year-old man to death while he was drunk. Now, in effect, he is simply stating, ‘My brain made me do it’, and there may be some neuroscientific basis for that. As it turns out, Yepez has what’s known as an MAO‑A gene variant. This has been known as the ‘warrior gene’ and can lead to uncharacteristically aggressive behavior.
So while you’re pondering whether that really has some basis in fact or is just some criminal defense attorney’s creative mind gone awry, ask yourself this question. If you’re walking down the street and somebody coming toward you suddenly has an epileptic seizure and strikes you with his hand or leg, would you want him arrested for the battery? How about if somebody goes into a diabetic coma while driving and hits the back of your car … a reckless driving charge? Would you feel differently if it was his first diabetic event or if he just failed to take his insulin and had half a doughnut in his hand?
In my death penalty work, I have utilized PET scans to show brain dysfunction in my clients either to diminish their ability to form specific intent to commit a crime or to mitigate against the imposition of the death penalty.
Can a genetic predisposition or malfunction lay the foundation for a defense to a criminal act? Since it is something capital jurors are to consider in determining whether or not to impose the death penalty, why shouldn’t petit juries have the same opportunity in determining whether or not a specific intent to commit the crime has been affected?
This is not a get out of jail card for any criminal behavior, but in those very particular cases like the Yepez case, it may offer some insight.
The first time that PET scan evidence was allowed was in the State of New York v. Herbert Weinstein matter, where Mr. Weinstein, otherwise law-abiding 68‑year-old married man strangled his wife and threw her off an apartment balcony. He was found to have a significant brain cyst which compressed certain parts of his brain. While the issue was never finally resolved by a higher court because Weinstein was able to work out a plea offer on the eve of trial, the door had been cracked open.
With all this as a backdrop how incumbent is it upon criminal defense attorneys to review their fact patterns for evidence, subtle though it may be, that a client may have acted a certain way because of a brain malfunction, or a genetic predisposition? Must we now have a neuroscientist on our team, or at least available to us?
Concerning Mr. Yepez’ warrior gene, if he and everyone else with a similar variant is predisposed towards violence, do we have an obligation to identify them ahead of time, not unlike the ‘precogs’ in Minority Report?
As neuroscience and gene mapping progresses, these are issues that our criminal justice system and our society as a whole is going to have to address and resolve. Stay tuned.