Ok, let's imagine we all agree that free will doesn't exist. Now what?
The notion that individuals should be punished for circumstances outside of their control is as problematic as jailing someone for getting the flu.
This isn’t to claim that criminal behavior is acceptable or that nothing should be done about it, but the change in understanding of the behavior itself would immediately demand a shift towards rehabilitation instead of punishment/vengeance.
Some people are still gonna have to be locked up, just like critically ill patients require ongoing care. But headlines like “scientists make breakthrough discovery in correcting brain chemistry that leads to sociopathy” will be as exciting as headlines about cancer cures.
Nope, I have no free will with which to choose to stop imprisoning people in horrible conditions.
Because what they're asking is "What if we could fundamentally change existence?" That's what it would take to perform these reforms without the existence of free will. Because people wouldn't have the choice to do whatever.
So while we would have to accept that not only are criminals incapable of doing anything different, but also the police are incapable of doing anything different, and the people hiring them, etc. Turtles all the way down.
Nothing changes.
This is an oversimplification/misreading of the philosophical ideas behind the notion that free will might not exist.
Proponents of the 'no free will' camp generally understand this to mean that we are not the conscious authors of our thoughts, and that thoughts are the product of one's lifetime of experiences and the result of those experience on one's specific biology.
In such a model of the world, the police would absolutely be capable of change, since knowledge is a potent change agent.
We already society is capable of this kind of change by looking at the history of slavery. A growing understanding of the value of each human life made the abolition of slavery a moral imperative for similar reasons. Such a cultural shift didn't happen overnight, though.
And if free will absolutely does not exist and we're just the results of the sum of our experiences, then it's also inevitable that the abolition of slavery was going to happen because that's the sum of the total.
Free will is binary. You can't have just a little of it. And if the argument is that a lot of what we do is unconscious, then that's not arguing against free will. That's arguing against something else.
This is as preventative, restorative and rehabilitative as it could ever be?
> Some people are still gonna have to be locked up
The point is not that people do not need to be deterred, but that the nature of that deterrence and the policies related to locking people up must change with such a revelation.
Such a revelation would also explain rates of recidivism, and shine a light on how counterproductive our current policies most likely are.
As we learn more about the brain, some form of this is already playing out. Accused criminals have been exhonerated on account of tumors growing on their brains, the removal of which returned the individual to “normal”.
Tumors are obvious, but as we learn more, I suspect we’ll find that many forms of criminality may be treatable.