The fact that Europe ruled the world when it hanged it's unwanted; and the fact that its now a shithole hellscape because it doesn't proves it works.

Remove the worthless, society will flourish. It's not complicated

It's not a controversal theory, though I'm sure they would not have taught it to you in school or the media. However, real scientists agree that there is a genetic component, and what they're willing to admit is just a part I'm sure.

According to BraveAI summary:

"The most cited variant is the MAOA gene (often nicknamed the "warrior gene" or, inaccurately, the "serial killer gene"). Located on the X chromosome, the low-activity variant (MAOA-L) results in reduced breakdown of neurotransmitters like serotonin and dopamine. This can lead to heightened impulsivity and aggression, particularly when combined with adverse environmental conditions like mistreatment or stress.

Other genes linked to increased risk include CDH13 (associated with neural connectivity and ADHD) and dopamine-related genes like DAT1 and DRD2. Studies suggest that while genetics account for approximately 50% of the variance in aggressive behavior, the remaining 50% is attributed to environmental influences. Most individuals carrying these risk variants do not commit violent crimes, and the presence of these genes is not considered a definitive legal defense for criminal acts. "

Yep. That's how they got rid of crime. They hung the ones that had the gene for it. Can't be found today and there isn't any crime there.