I am a pretty simple person and I would recommend intensive psychological treatment and a lifelong supervision. Yes he is a child and was failed, but IMO you still have a choice and even smaller kids can tell the difference between right from wrong
There’s a lot to unpack in this article:
Learning Right From Wrong
The fragile steps toward a child's understanding that lying, stealing, cheating and hurting are out of bounds.
by Sharon Begley and Claudia Kalb
To the legal system, the answer is clear: children have the requisite moral sense--the ability to tell right from wrong--by age 7 to 15, depending on which state they live in, and so can be held responsible for their actions. The Roman Catholic Church pegs it at the early end of that range: children reach the "age of reason" by the tender age of 7, a milestone marked by their first confession of sin and holy communion. Developmental psychologists and other researchers who study the question are not so sure. How old a child must be to both know in his mind and feel in his heart that lying, stealing, cheating, hurting--let alone murdering--are morally wrong is a matter of scientific debate.
But the question of when is not nearly so fraught as the question of how. Although they pretty much agree that living in a crack house--with people who respond to challenges with violence, and bereft of parental love, supervision and models of moral behavior--can leave a child's conscience stillborn, scientists are struggling toward a definitive answer to the question of how children develop a sense of right and wrong. "If there is any consensus, it is that conscience is a combination of head, heart and hand," says Marvin Berkowitz, professor of character development at the University of Missouri, St. Louis. "It is knowing the good, loving the good and doing the good. And that requires both cognitive and emotional components."
The emotional piece falls into place first. "All children are born with a running start on the path to moral development," says psychologist William Damon of Stanford University. The reason is that empathy, the key emotion supporting a sense of right and wrong, emerges early and, it seems, naturally. Babies cry in response to the wails of other babies, "and not just because it's a sound that upsets them," notes Carolyn Zahn-Waxler of the National Institute of Mental Health. "They cry more in response to human cries than to other aversive sounds. Somehow, there's a built-in capacity to respond to the needs of others." Babies as young as 1 try to console others in distress. Toddlers offer their security blanket to a teary-eyed parent or a favorite toy to a distraught sibling, as if understanding that the very object that brings them comfort will do the same to another.
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Heart and head will take a child only so far, however. "I suspect that if you sat down [the first-grade shooter] when he was quiet and calm, before this happened, and asked, 'Is it bad to shoot someone?' he would have said yes," says psychologist Laurence Steinberg of Temple University and director of a MacArthur Foundation program on juvenile justice. How much he understood about the consequences of shooting and the finality of death is unknown. But choosing not to undertake a horrific act requires the third ingredient of conscience: a gut-wrenching aversion to wrong. "Gut-wrenching" is not merely a figure of speech: it means the racing heart, sweaty palms and churning stomach that moral individuals would feel if forced to, say, burglarize a house. Some people simply lack this stress response, but probably not because of a genetic defect. When Adrian Raine of the University of Southern California recorded how 15-year-olds' heart rates, EEGs (a measure of brain activity) and other factors changed in response to stress, he found some cool customers who were not fazed by anything. Compared with kids with a normal stress response, they had a greater chance of being criminals at the age of 24. Perhaps low arousability makes kids seek out excitement and danger, Raine suggests. Or maybe it makes them fearless. "Kids who come from a bad home environment, who are battered from pillar to post, may become inoculated to stress," says Raine. "Their nervous system may simply not be wired to ring a warning bell" when they are about to do something dangerous--or wrong. This brain wiring may be what's missing in kids who "know" right from wrong but fail to act on it.
When do the heart, the head and the gut come together to produce, if not a moral philosopher, at least a moral child? "My hunch is that it's probably not complete until a child is close to 12," says Steinberg. "But a lot of these things are still developing at 15." And sometimes, as any glance at the headlines will tell you, they fail to develop at all.