The Free Will Confusion (1): On “My Brain Made Me Do It!”

Is neuroscience able to overthrow our moral and legal system? Does the reference to brain causation morally or legally excuse one’s misdeeds? This psychophilosophical analysis explains why “My Brain Made Me Do It!” is no excuse.

Since roughly a decade, scholars wold-wide are discussing whether neuroscience may undermine the moral and legal foundations of our society. Some claim or fear that inasmuch as causes of our behavior are discovered in the brain, we will hold people less responsible and thus also less blame- or praiseworthy for their (mis-)deeds. Actually there is even a new field called “neurolaw” which is devoted to such issues – but also much more practical questions such as whether lie detection is possible with neuroscience means. Two acquaintances of mine just recently edited books on this, Tade Spranger’s International Neurolaw (Springer) and Nicole Vincent’s Neuroscience and Legal Responsibility (forthcoming with Oxford University Press), and the International Journal of Law and Psychiatry just had a respective special issue devoted to neuroscience and law, including an article of mine.

There have been deterministic frameworks before...

Some people dramatized the possible impact of neuroscience and predicted a neuro-revolution (see, e.g., Zack Lynch’s corresponding book, critically reviewed by me here). Regarding its capacity to shake our moral and legal system, a bit of historical background might be illuminating. Already philosophers of the Stoa in Greek and Roman antiquity thought that our behavior was determined by natural law. Later Christian theological philosophers discussed several variants of divine predetermination and in the course of the 19th century there was a materialism dispute in the wake of new discoveries of the sciences interpreted to show that humans are nothing more than sophisticated machines, that what the urine is to the kidneys, the mind is to the brains, as the physiologist Carl Vogt (1817-1895) once wrote (the original German formulation of 1854 can be found here).

So the late 20th and early 21st century is not the first period to understand human beings as embedded into the causal flow of nature and many great scientists and philosophers have discussed whether this view can be reconciled with a sophisticated idea of human freedom. Furthermore, philosophers of mind have discussed many variants of so-called identity or reductionistic theories during the last decades, doctrines which equate the mind with the brain or want to explain psychological processes sufficiently and exclusively in terms of brain processes.

...yet there was no neuro-revolution

All this happened, obviously, without ever overthrowing our social order; there were no social neuro-reverberations so far that could even slightly be compared with the ramification of, say, recent financial crises. No people on the streets, protesting that morals and law are unjust, holding people responsible when, in fact, they aren’t. It is a question of its own whether recent neuroscience contributed something genuinely new to this debate, a question I am going to discuss in one of the later posts of this series on the Free Will Confusion. Let’s stick to the legal system for the time being and question whether causes in the brain would excuse people who have committed crimes, who would claim, in other words, that their brains made them do it.

A few weeks ago, two psychologists, John Monterosso at the University of Southern California, and Barry Schwartz at Swarthmore College had a related op-ed in the New York Times.* In the context of the recent neuroscience & law debate they warn that people might be subject to what they coined “naïve dualism”, a distinction between psychological and brain causes. Indeed, they published a carefully carried-out behavioral study called "Explaining Away Responsibility" in which they varied three factors in vignettes describing criminal (arson, murder) or otherwise possibly problematic (overeating, not being enduring) behavior. The three factors were, first, uniformity, i.e. how likely people with a certain characteristic are to show the behavior, second, deterrence, i.e. whether people were responsive to the considered consequences of their actions, and, third, the explanatory framework, i.e. whether their behavioral disposition was explained in terms of social or physiological causes.

Brain-causes misunderstood to excuse

Making a longer story short, when people judged the culpability of the behaviors, the third factor, explanatory framework, had the strongest effect on the ratings; and, indeed, the behaviors were considered as less culpable when explained in a physiological instead of a social framework. In their own words, in their vignettes

when a physiological explanation was given, participants tended to view the body as the cause of the behavior and motivations as less relevant, with the result that the behavior was perceived as less voluntary. (Monterosso, Royzman & Schwartz, 2005, p. 155)

So, for example, when they had to judge the murderer Joe who had “repeatedly kicked [a clerk] in the head after he had fallen to the ground”, people found this crime less culpable when they were given the information that Joe had a chemical imbalance related to violence than when they were told that he had been severely abused as a child, also making violent acts more probable. We should be aware, though, that as so often in science (and as so often omitted in science communication), we are not dealing with an all-or-nothing difference here. On a five-point scale to indicate blame, the average values for the social and physiological explanations were 3.78 and 3.43, respectively. So people found the murder generally blameworthy in both cases, just to a lesser degree when it was related to the chemical imbalance in the brain than to the experienced childhood abuse.

Causal acts don't excuse and random act's don't inculpate

Monterosso and Schwartz criticize this distinction, and in my view rightly so. Not just neuroscience, but also psychology and sociology have investigated causes of human behavior, actually long before the invention of brain scanners. The experience of child abuse of the (imagined) Joe would have effected his brain, and if he had had a chemical brain imbalance, that could have been due to child abuse or other social, genetical, or neural happenings. We can also put the question differently: If we thought that causation excused people, what would actually inculpate them? Genuinely uncaused random acts? No, the legal distinction is not that between caused and uncaused, deterministic and indeterministic acts, but between acts that are subject genuinely excusing conditions or not. Stephen Morse at the University of Pennsylvania has not become tired of explaining that

in a world of universal causation or determinism, causal mechanisms are indistinguishable in this respect and biological causation creates no greater threat to our life hopes than psychological or social causation. For purposes of the metaphysical free will debate, a cause is just a cause, whether it is biological, psychological, sociological, or astrological. (Morse, 2007, p. 213)

In the current context, one could actually interpret Justitia's scales as a symbol that there is no general difference between brain, psychological, or sociological causes when assessing someone's legal responsibility.

In the same paper with the telling title “The non-problem of free will in forensic psychiatry and psychology” Morse calls it a criterion of “free will confusion syndrome” to claim that causation excuses or mitigates responsibility. In quite a number of legislations world-wide people are considered as legally responsible as long as they are minimally rational which means, roughly, that they are sufficiently capable of controlling themselves and knowing the nature and the wrongness of the act.

So, under certain conditions of compulsion or mental delusion, for example when somebody convincingly threatens to wipe out one’s family unless one commits a certain crime (say, smuggle that package of cocaine over the boarder), or when one is in a delusional state and believes that one’s boss is obsessed by an evil demon and going to kill mankind unless stopped violently, then one may indeed be legally excused; but in neither case goes the argument that the action was uncaused. By contrast, both cases describe causes that may be recognized as excusing conditions, namely compulsion or delusion.

Causation does not threaten our social order

So even if neuroscientists were able to identify perfect causes for all of our actions, which currently they cannot and we can only speculate on whether they will be ever able to do so, this would not threaten the foundations of our moral or legal systems. Particularly in countries where juries are assigned to judge somebody’s responsibility or blameworthiness for a crime, though, Monterosso’s and Schwartz’s critique of “naïve dualism” should be taken seriously and the members of the juries should be informed that brain causation in no way excuses or inculpates more or less than social causation. Yet I would doubt that criminal court judges are subject to the same bias, although I admit that also judges’ decision-making sometimes is less than perfect, as for example the work (PDF) of a collaborator of mine, Birte Englich at the University of Cologne, has shown.

Unfortunately though, there sometimes are cases where even judges can be confused by scientific data. In two decisions made by Italian judges in 2009 and 2011 (reported in Nature here and here, and commented on by me [in German] here and here) genetic and neuroscience information has been used to reduce the sentences of two murderers. But the issue here is not that between causation or non-causation, but whether that scientific evidence validly indicates the presence of a genuinely excusing condition. To not make this post even longer, let me just summarize that in one of the decisions such evidence was considered to indicate the presence of a psychiatric condition, while it is generally acknowledged that currently not a single psychiatric disorder can actually be diagnosed with such means. This shall be a topic for another time.

Avoid free will confusion disorder

I hope that you have learned by now that causation is not the issue when assessing someone’s legal or moral responsibility. According to the present majority’s metaphysical framework, psychological processes are realized in the brain and no magic is involved when one’s action or state is due to a psychological or social condition, such as feeling sad when losing one's job or feeling good when dancing at a Latin music party; and for this very reason, neuroscience cannot threaten our psychology or sociology by identifying the corresponding neural mechanisms of such conditions.

Photo credit: Florentine / pixelio.de

* Please note that there is a mistake in the New York Times article. The Supreme Court decision of 2005 (Roper v. Simmons), written by Justice Kennedy, made no single reference to brain research. Only in a related decision of 2010 (Graham v. Florida), the judge referred to neuroscience but it is arguable whether this reference added anything to the argument, here, on whether it is constitutional to give juveniles a life sentence without the possibility of parole.