Are Psychopaths Mad or Bad?

Psychopaths who commit violent crimes are evil, not legally insane.

Posted Sep 29, 2019

A standing question in relation to psychopaths who commit violent crimes is whether they should be excused on grounds of insanity or be punished like other violent criminals. A defense on the grounds of insanity must adhere to the M’Naghten Rules:

[T]o establish a defense on the grounds of insanity, it must conclusively be proved that, at the time of committing the act, the party accused was laboring under such a defect of reason, from disease of the mind, as not to know the nature and quality of the act he was doing; or if he did know it, that he did not know what he was doing was wrong. (The M’Naghten Rules)

The insanity defense is generally not available to psychopaths under U.S. legislation, because they fail to satisfy the conditions outlined in the M’Naghten Rules. They can identify and provide full details of the crimes they committed, and they know that carrying out actions of this nature is legally wrong.

Psychotic criminals, by contrast, don’t understand why their actions are wrong. A paradigm example of a psychotic killer is Coral Eugene Watts, who strangled as many as 80 women. Watts was mentally retarded with an IQ of 75. He basically had the mental capacity of a slow third grader.

In addition to that, Watts suffered from delusions and hallucinations. When asked about his murders, he insisted that his victims were already dead when he strangled them, because the devil had taken possession of their bodies and had consumed their souls. There is no doubt that Watts’ mental impairments compromised his ability to understand the wrongness of his actions.

Psychopaths are not in the grip of a hallucination or delusion that causes them to think that someone else is acting through them or that prevents them from seeing the wrongness of their actions.

U.S. courts allow exculpation from punishment for some of the most mentally disturbed psychotic or retarded criminals on the grounds of insanity, but not for psychopaths, because psychopaths know what they have done and understand why the actions they committed are prohibited by law. For this reason, their deficits do not justify a defense on the grounds of insanity.

Philosophers have challenged this line of thought. Philosopher David Shoemaker has argued that the nature of the mental impairments observed in psychopaths exculpates them from criminal and moral responsibility.

The gist of the argument is this: While psychopathic criminals can provide full details of the crimes they have committed and know what they have done is illegal, they lack the kind of deep moral understanding needed to fully comprehend the wrongness of their actions.

Deep moral understanding requires empathy. As psychopaths lack the capacity for empathy, they lack the deep moral understanding necessary for criminal responsibility. So, psychopathy justifies an insanity defense, under the M’Naghten Rules. Or so the argument goes.

Psychopaths do indeed lack the capacity for one kind of empathy. For example, when observing others in distress, they present with reduced skin conductance and startle responses. The question is whether the empathy they lack is the kind of empathy needed for deep moral understanding. 

Here we need to distinguish between two kinds of empathy: cognitive empathy and emotional empathy (Bloom, 2016; Maibom, 2008). Cognitive empathy, also known as social cognition or mind-reading, is the ability to take another person’s perspective and make reasonable estimates about what they feel, think and intend to do. Emotional empathy is the experience of emotional pain in response to another person’s suffering, or the experience of pleasure in response to another person’s well-being or good fortune.

Psychopaths' reduced physiological responses to seeing other people in distress show that they probably don't experience the same degree of emotional empathy as most other people do. In other words, they don't feel distress in response to other people's suffering.

But this has no bearing on the question of whether they lack cognitive empathy. In fact, psychopaths often seem to have particularly well-developed social cognition or mind-reading skills. So, when they make a victim suffer, they are perfectly able to see what things are like from the other person's perspective. They can predict the victim's next move, their willingness to obey them, their tendency to try to engage with them as human beings.

Psychopaths clearly understand that on a very deep level what their victims are going through, which is to say that they do have the kind of deep moral understanding required for them to understand what they are doing. So, psychopathy doesn't justify an insanity defense, under the M’Naghten Rules.


Shoemaker, D. (2017). “Empathy and Moral Responsibility.” In Routledge Handbook of Philosophy of Empathy, ed. H. L. Maibom, London and New York: Routledge: 242-252.

Maibom, H. L. (2008). “The Mad, the Bad, and the Psychopath,” Neuroethics, 1(3): 167-184.

Bloom, P. (2016). Against Empathy: The Case for Rational Compassion, New York: Ecco.