Wheel chairs and walkers sit outside prison cells

The United States must not allow the execution of a murderer who cannot remember his crime.Credit: Andrew Burton/Getty

In 1985, Vernon Madison shot a police officer in the back of the head while the officer sat in his car. It was a heinous crime for which Madison has spent the past 33 years on death row, much of it in solitary confinement.

But Madison now doesn’t remember the Alabama shooting or the name of the officer — he can remember very little at all. Multiple strokes in the past few years have wiped out parts of his brain involved in memory and left him with vascular dementia. Madison’s lawyers have appealed against his death sentence, and presented his case before the US Supreme Court earlier this week.

The case raises complex philosophical, legal and ethical questions about the purpose of the death penalty and what it means to truly understand one’s own guilt. In taking the case, the court accepted the task of deciding whether it is cruel and unusual to execute a violent murderer who doesn’t understand his fate, even if he understood the possible consequences at the time the crime occurred.

The evidence of Madison’s cognitive disability is convincing. In neuropsychological tests administered by multiple specialists, he can’t interpret the meaning of stories or logically draw conclusions. His lawyers say that, in terms of his intellectual function, there is no difference between his current condition and that of a person born with an intellectual disability. The latter group is protected from execution, thanks to a 2002 Supreme Court decision.

Madison’s case differs because he did not have a severe cognitive impairment at the time he committed the murder, and presumably knew it was wrong. The state of Alabama argues that once the situation is explained to him, Madison also understands that he was tried and will be executed. Alabama says it doesn’t matter whether he remembers it, because he can still rationally conceptualize it.

But psychologists and psychiatrists say that this is very different from a deep understanding of one’s own guilt. Ultimately, the court will have to determine what level of ‘understanding’ is sufficient to conclude that Madison can rationally process his punishment.

Science cannot offer all the answers in this specific case. Still, decades of research on neuropsychology — much of it done to better understand mental-health conditions — have honed the ability of specialists to understand brain function. In a joint amicus brief filed to the Supreme Court, the American Psychiatric Association and the American Psychological Association say that neuropsychological tests and advances in neuroimaging can accurately assess cognitive capacity, precluding any concerns that in the future, courts might see a flood of appeals from people who falsely claim to have no memory of their crime.

The court could issue a narrow decision that applies only to Madison, or it could rule broadly on people who cannot understand the reason for punishment. Although there are probably very few people on death row with vascular dementia, conditions such as traumatic brain injury or tumours could cause a person to forget a crime.

The case highlights the illogic of capital punishment. Death-penalty proponents argue that it is necessary for justice to be served, as well as to deter others from crime. Yet neither of these conditions applies here. Madison cannot see his execution as justice because he cannot recall his crime. And executing a person with an intellectual disability hardly serves as an example or deterrent.

Regardless of the decision, Madison is not going unpunished. If he escapes execution, he will spend the rest of his life in prison alone, disabled and confused by the world around him. He is no longer a threat. The court should set an example and grant mercy.