LOPEZ: Why did you dedicate the book to James Q. Wilson?
SATEL: Not only do I admire James Q. Wilson greatly, I had the honor to know him through AEI, where he was the chairman of the academic advisory council. In his 1993 book, The Moral Sense, Wilson was impatient with moral relativism and the idea that man was primarily a product of his culture. He argued that a moral sense was part of our basic nature, rooted in evolutionary biology, yet he took issue with the over-correction to cultural determinism borne by rigid biological explanations of human behavior. In recent years, Wilson was writing about genetic determinism and had just begun to write about neurodeterminsim. I think that he would have turned more fully to popular brain science and its excesses as the next phase of his interest in “the moral sense.”
LOPEZ: “When a person commits a crime, who is at fault: the perpetrator or his or her brain?” You accuse this question of a “false distinction.” But what if the perpetrator is mentally ill? Wouldn’t it only be fair and just to make the distinction?
SATEL: The law does indeed accommodate people with severe mental illness whose rationality is seriously impaired as a consequence of the illness. The insanity defense may apply to such individuals. More generally, it is important to understand the relationship between cause and excuse under the law. The law’s concept of the person is that of an agent who is capable of acting at will and of offering reasons for his or her actions. Rationality is the hallmark of responsibility. There may be myriad reasons why people commit crimes, but no matter the explanation — from bad neurons to bad parents to bad stars — defendants will be found legally blameworthy as long as their rational capacity remains largely intact. Obviously, if causation alone served to excuse behavior, then all behavior would need to be excused, and no one could ever be held responsible for his or her actions. Biological causes are accorded no special weight in the eyes of the law, even though many people harbor the intuition that they should wield more clout.
LOPEZ: Was the Supreme Court’s verdict in Roper v.Simmons based on revelations in brain science?
SATEL: The 2005 Simmons ruling banned the execution of offenders whose crimes were committed before age 18. There is little to no evidence that the Court ruled in this manner on the basis of presented evidence that the teen brain is biologically immature, yet many juvenile-justice advocates credited the brain science with persuasive power.
The majority of the justices were right to regard the neurobiological evidence as telling them nothing new about teen behavior. After all, Christopher Simmons — a teen who killed a woman after breaking into her home — did not need to possess a fully formed brain to know that throwing a hog-tied person off a bridge is wrong. An average nine-year-old grasps the finality of death. Although the neuroscience of the adolescent brain helps us construct a plausible biological account of why adolescents can be more impetuous than adults, it says little about any individual teen offender. A case-by-case approach makes the most sense. To be sure, there are compelling ethical reasons for eliminating the death penalty for juvenile killers. But the idea that the neurobiology of their collective brains should categorically exclude teens from certain forms of punishment is a shaky proposition.
LOPEZ: “The vast majority of teens who harbor fantasies of violence do not act on them,” you write. Then do we need to rethink some of our strategies about deciphering warning signs?
SATEL: The best predictor of future behavior is usually past behavior. It’s an old rule of thumb but it’s still true. Efforts are underway to try to predict violence by detecting patterns of brain activity, but such “neuro-prediction,” as it is called, is not yet fit for use. The accuracy is too low and thus too many nonviolent people are classified as potentially violent.
A few months ago, researchers reported that reduced activity in a region of the brain called the anterior cingulate cortex (ACC) could predict subsequent rearrest among adult offenders within four years of release. But the prediction was far from perfect. Forty percent of the reduced-ACC-activity parolees did not reoffend and 46 percent of higher-ACC parolees did. The study was impressive (good sample size, great follow-up with subjects), but who would seriously dream of breaching a person’s liberty based on findings that are so imprecise? Not the authors of the paper, as they made clear.
But, maybe we’ll get a lot better at prediction. I’m skeptical that we’ll ever get good enough — and how good is good enough? 90 percent? 99.99999 percent? — to justify detaining people prior to the commission of a crime. But the key lesson here is that the issue of where to draw the line on an acceptable level of risk is not a scientific one. Data inform these decisions, but, in the end, they come down to deliberation among citizens, experts, and policymakers.
Predicting violent behavior in teens or adults will always be hard because there is such a low base rate of these behaviors and the risk of false positives (thinking you’ve detected a future mass killer when you haven’t) is so high. As far as school-based disasters go, it seems that efforts are best directed at facilitating communication among students and faculty because it is often the case that students who plan mayhem tell their friends.