Emily Cataneo in Undark:
IT’S 1922. You’re a scientist presented with a hundred youths who, you’re told, will grow up to lead conventional adult lives — with one exception. In 40 years, one of the one hundred is going to become impulsive and criminal. You run blood tests on the subjects and discover nothing that indicates that one of them will go off the rails in four decades. And yet sure enough, 40 years later, one bad egg has started shoplifting and threatening strangers. With no physical evidence to explain his behavior, you conclude that this man has chosen to act out of his own free will.
Now, imagine the same experiment starting in 2022. This time, you use the blood samples to sequence everyone’s genome. In one, you find a mutation that codes for something called tau protein in the brain and you realize that this individual will not become a criminal in 40 years out of choice, but rather due to dementia. It turns out he did not shoplift out of free will, but because of physical forces beyond his control.
Now, take the experiment a step further. If a man opens fire in an elementary school and kills scores of children and teachers, should he be held responsible?
More here.