The Seductive Slippery Slope of using Science to Predict “Bad” Behavior

Original article was published by Andrew Maynard on Artificial Intelligence on Medium


In the seventeenth century, a very different “science” of predicting criminal tendencies was all the rage: phrenology. Phrenology was an attempt to predict someone’s character and behavior by the shape of their skull. As understanding around how the brain works developed, the practice became increasingly discredited. Sadly, though, it laid a foundation for assumptions that traits which appear to be common to people of “poor character” are also predictive of their behavior — a classic case of correlation erroneously being confused with causation. And it foreshadowed research that continues to this day to connect what someone looks like with how they might act.

Despite its roots in pseudoscience, the ideas coming out of phrenology were picked up by the nineteenth-century criminologist Cesare Lombroso. Lombroso was convinced that physical traits such as jaw size, forehead slope, and ear size were associated with criminal tendencies. His theory was that these and other traits were throwbacks to earlier evolutionary ancestors, and that they indicated an innate tendency toward criminal behavior.

It’s not hard to see how attractive these ideas might have been to some, as they suggested criminals could be identified and dealt with before breaking the law. With hindsight, it’s easy to see how misguided and malevolent they were, but at the time, many people bought into them. It would be nice to think that this way of thinking about criminal tendencies was a short and salutary aberration in humanity’s history. Sadly, though, it paved the way to even more divisive forms of pseudoscience-based discrimination, including eugenics.

In the 1900s, discrimination that was purportedly based on scientific evidence shifted toward the idea that the quality or “worth” of a person is based on their genetic heritage. The “science” of eugenics — and sadly this is something that many scientists at the time supported — suggested that our genetic heritage determines everything about us, including our moral character and our social acceptability. It was a deeply flawed concept that, nevertheless, came with the same seductive idea that, if we know what makes people “bad,” we can remove them from society before they cause a problem. What is heartbreaking is that these ideas coming from academics and scientists gained political momentum, and ultimately became part of the justification for the murder of six million Jews, and many others besides, in the Holocaust.

These days, I’d like to think we’re more enlightened, and that we don’t fall prey so easily to using scientific flights of fancy to justify how we treat others. Unfortunately, this doesn’t seem to be the case.

In 2011, three researchers published a paper suggesting that you can tell a criminal from someone who isn’t (and, presumably by inference, someone who is likely to engage in criminal activities) by what they look like. In the study, thirty-six students in a psychology class (thirty-three women and three men) were shown mug shots of thirty-two Caucasian males. They were told that some were criminals, and they were asked to assess — from the photos alone — whether each person had committed a crime; whether they’d committed a violent crime; if it was a violent crime, whether it was rape or assault; and if it was non-violent, whether it was arson or a drug offense.

Within the limitations of the study, the participants were more likely to correctly identify criminals than incorrectly identify them from the photos. Not surprisingly, perhaps, this led to a slew of headlines along the lines of “Criminals Look Different From Non-criminals” (this one from a blog post on Psychology Today). But despite this, the results of the study are hard to interpret with any degree of certainty. It’s not clear what biases may have been introduced, for instance, by having the photos evaluated by a mainly female group of psychology students, or by only using photos of white males, or even whether there was something associated with how the photos were selected and presented, and how the questions were asked, that influenced the results.

The results did seem to indicate that, overall, the students were successful in identifying photos of convicted criminals in this particular context. But the study was so small, and so narrowly defined, that it’s hard to draw any clear conclusions from it. However, there is a larger issue at stake with this and similar studies, and this is the ethical issue with carrying out and publicizing the results of such research in the first place. Here, the very appropriateness of asking if we can predict criminal behavior brings us back to the earlier study on intent versus reckless behavior, and to the underlying premise in Minority Report.

The assumption that someone’s behavioral tendencies can be predicted from no more than what they look like, or how their brain functions, is a slippery slope. It assumes — dangerously so — that behavior is governed by genetic heritage and upbringing. But it also opens the door to a better-safe-than-sorry attitude to law and order that considers it better to restrain someone who might demonstrate socially undesirable behavior than to presume them innocent until proven guilty. And it’s an attitude that takes us down a path where we assume that other people do not have agency over their destiny. There is an implicit assumption here that how we behave can be separated out into “good” and “bad,” and that there is consensus on what constitutes these. But this is a deeply flawed assumption.

What the behavioral research above is actually looking at is someone’s tendency to break or bend agreed-on rules of socially acceptable conduct, as these are codified in law. These laws are not an absolute indicator of good or bad behavior. Rather, they are a result of how we operate collectively as a social species. In technical terms, they establish normative expectations of behavior, which simply means that most people comply with them, irrespective of whether they have moral or ethical value. For instance, in most cultures, it’s accepted that killing someone should be punished, unless it’s in the context of a legally sanctioned war or execution (although many societies would still consider this morally reprehensible). This is a deeply embedded norm, and most people would consider it to be a good guide of appropriate behavior. The same cannot be said of “norms” surrounding homosexual acts, though, which were illegal in the United Kingdom until 1967,
and are still illegal in some countries around the world, or others surrounding LGBTQ rights, or even women’s rights.

When social norms are embedded within criminal law, it may be possible to use physical features or other means to identify “criminals” or those likely to be involved in “criminal” behavior. But are we as a society really prepared to take preemptive action against people who we arbitrarily label as “bad”? I sincerely hope not. And here we get to the crux of the ethical and moral challenges around predicting criminal intent. Even if we can predict tendencies from images alone — and I am highly skeptical that we can gain anything of value here that isn’t heavily influenced by researcher bias and social norms — should we? Is it really appropriate to be asking if
we can predict, simply from how someone looks, whether they are likely to behave in a way that we think is appropriate or not? And is it ethical to generate data that could be used to discriminate against people based on their appearance?

Using facial features to predict tendencies puts us way down the slippery slope toward discriminating against people because they are different from us. Thankfully, this is an idea that many would dismiss as inappropriate these days. But, worryingly, our interest in relating brain activity to behavioral traits — the high-tech version of “looks like a criminal” — puts us on the same slippery slope.

Criminal Brain Scans

Unlike photos, functional Magnetic Resonance Imaging allows researchers to directly monitor brain activity, and to do it in real time. It works by monitoring blood flow to different parts of the brain, and using this to pinpoint which parts of someone’s brain are active at any one point in time.

One of the beauties of fMRI is that it can map out brain activity as people are thinking about and processing the world around them. For instance, it can show which parts of a subject’s brain are triggered if they’re shown a photo of a donut, if they are happy, or sad, or angry, or what their brain activity looks like if they’re given the opportunity to take a risk.

fMRI has opened up a fascinating window into how we think about and respond to our surroundings, and in some cases, what we think. And it’s led to some startling revelations. We now know, for instance, that we often unconsciously decide what we’re going to do several seconds before we’re actually aware of making a decision. Recent research has even indicated that high-resolution fMRI scans on primates can be used to decode what the animals are seeing. The researchers were, quite literally, reading these primates’ minds.

This is quite incredible science. And not surprisingly, it’s leading to a revolution in understanding how our brains operate. This includes developing a better understanding of how certain brain behaviors can lead to debilitating medical conditions. It’s also leading to a deeper understanding of how the mechanics of our brain determine who we are, and how we behave.

That said, there’s still considerable skepticism around how effective a tool fMRI is and how robust some of its findings are. It’s also fair to say that some of these findings challenge deeply held beliefs about many of the things we hold dear, including the nature of free will, moral choice, kindness, compassion, and empathy. These are all aspects of ourselves that help define who we are as a person. Yet, with the advent of fMRI and other neuroscience-based tools, it sometimes feels like we’re teetering on the precipice of realizing that who we think we are — our sense of self, or our “soul” if you like — is merely an illusion of our biology.

This in itself raises questions over the degree to which neuroscience is racing ahead of our ability to cope with what it reveals. Yet the reality is that this science is progressing at breakneck speed, and that fMRI is allowing us to dive ever deeper behind our outward selves — our facial features and our easily observed behaviors — and into the very fabric of the organ that plays such a role in defining us. And, just like phrenology and eugenics before it, it’s opening up the temptation to interpret how our brains operate as a way to predict what sort of person we are, and what we might do.