The Brain on Trial

David Eagleman thinks that advances in neuroscience should transform our criminal justice system. Writing in The Atlantic, Eagleman emphasizes how genetic and environmental factors influence cognitive function:

We are each constructed from a genetic blueprint, and then born into a world of circumstances that we cannot control in our most-formative years. The complex interactions of genes and environment mean that all citizens—equal before the law—possess different perspectives, dissimilar personalities, and varied capacities for decision-making. The unique patterns of neurobiology inside each of our heads cannot qualify as choices; these are the cards we’re dealt.

Because we did not choose the factors that affected the formation and structure of our brain, the concepts of free will and personal responsibility begin to sprout question marks. Is it meaningful to say that Alex made bad choices, even though his brain tumor was not his fault? Is it justifiable to say that the patients with frontotemporal dementia or Parkinson’s should be punished for their bad behavior?

It is problematic to imagine yourself in the shoes of someone breaking the law and conclude, “Well, I wouldn’t have done that”—because if you weren’t exposed to in utero cocaine, lead poisoning, and physical abuse, and he was, then you and he are not directly comparable. You cannot walk a mile in his shoes.

The legal system rests on the assumption that we are “practical reasoners,” a term of art that presumes, at bottom, the existence of free will. The idea is that we use conscious deliberation when deciding how to act—that is, in the absence of external duress, we make free decisions. This concept of the practical reasoner is intuitive but problematic.

The “practical reasoner” assumption is, of course, fundamental to much of economics as well. Used thoughtfully, it’s extremely useful for examining how reflective, ends-oriented agents behave. But it’s problematic, to say the least, if we assume that everyone is always a rational actor.

Eagleman argues that the criminal justice system should be sensitive to the cognitive differences among people. Some people murder as the result of calculated, rational decisions, but others murder because brain tumors destroy their ability to control themselves. Those differences matter when thinking about deterrence, treatment, and punishment.

4 thoughts on “The Brain on Trial”

  1. Mr. Eagleman seems more informed about how the brain works than the legal system. In fact, factors cited by him are already taken into account. Insanity, diminished capacity due to any number of factors, etc, have long been taken into account to determine not only culpability, but also the degree of such culpability. And, these factors are taken into account in the sentencing stage. Courts have even been known to consider the effects of sugar on the brain. Today, psychologists play a greater role in assessing guilt, and the degree thereof, than lawyers do.

    So, the legal system is already “sensitive to these factors” and many would argue too much so. Perhaps what Mr. Marron meant to say in summarizing Eagleman’s argument is that the system should be even “*more* sensitive”?

  2. One perhaps has to consider the difference between the mental processes and actions of individuals and the needs of society. If someone is a danger to society, they need to be removed from a position where they can cause damage to others, regardless of whether they are a coldly rational murderer or a victim of diminished mental capacity.

    From an economics perspective, the “Invisible Hand” functions well when the actions of multitudes are being aggregated, equivalent to the statistical concept of the “Central Limit Theorem”, where the sum of a large number of variables will be reasonably normal even if the individual variables are not. This fails in the economy when a small number of individuals can independently shift outcomes (think leveraged hedge funds)…


  3. Bankers alone are reason enough to bring back public hangings. The disconnect between illegal behaviour and actual criminal punishment in the white collar world are so disparate that most think they are above the law.

    If I steal a tank of gas worth 30$, I’ll at the least get arrested,jailed, likely fined possibly imprisoned. If a banker steals a million dollars no one notices, if he steals a billion he might have a civil fine, admit no wrong doing and perhaps pay a proportionaly small fine using funds from his company, thereby reducing profits for shareholders.

    This then is the dilemma of justice in the 21st century. We severely punish the petty criminals because the justice system is owned by the biggest criminals.

    Timothy Leary showed that criminal recidivism could be mitigated and outright destroyed with the proper use of LSD and therapy, while he was a Harvard professor and LSD was legal and proper and the banks were so much smaller.

    If the brain is on trial, then surely the largest criminal class in the history of the world by dollars stolen alone, should be subjected to Professor Leary’s proven techniques. Those who are not rehabilatatable should perhaps be hung in a public spectacle and then their brains examined by science to determine the true nature of their pathology.

    Criminals can’t learn, but perhaps we can learn from criminals.Besides we have too many bankers and too few prison cells.

  4. I agree with the writter here, especially when he states “the dilemma of justice in the 21st century is we severly punish the petty criminals because the justice system in owned by the biggest criminals”, I however add that they will only sacarfice one of their own when that one has the gaul to steal from them.

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