Answer: No
Answer: No
The State killed a lot of people between the 14th and 20th centuries and also the homicide rate went down.
Wow!
QED
Good thing there weren't other major confounding changes between errmmm... the longbow and the atomic bomb. Or Dante's Divine Comedy and jazz.
I'm convinced. Why'd you even put the note "if not conclusive" with evidence this strong?
Note that Frost and Harpending are pretty conservative in their estimates; they figure only ballpark half the decline could be explained by this.
Case-control methods, natural experiments, surveys of criminals, and meta-analyses of the prior.
Literally any method other than "pick 600 year period and say 'vibes shifted generally across a continent and then homicide went down'"
Of course this question has been studied extensively for decades and the current conclusion is: completely inconclusive!
There's some evidence it increases violent crime, some that it decreases it, most evidence doesn't clearly show any effect at all.
So whatever effect it may have, it almost certainly isn't very strong, or is countervailed by opposing effects.
I think that if we're proposing the State, which we know to be fallible in so many cases, should make irreversible decisions like "executing suspected bad guys" more frequently, then we should have extremely strong evidence that it would actually achieve the desired result.
> It's also at least quasi-testable; someone could fund a study on examining alleles associated with aggression in historical remains.
Good luck establishing how "alleles associated with aggression" contributes to violence. I'm pretty sure most of the people who adopt your position would argue that their "aggressiveness" is a virtue in whatever competitive landscape they choose to occupy.
I think we're in violent agreement here; yes, this obviously bears further investigation. The way good science gets done is "We have some preliminary evidence that could support a certain hypothesis. We think people should do further investigation." Then you go do that further investigation to see if you can reject the null.
The alleles point, though, is weaker. You're not just looking at stuff like MAO-A activity, also CDH13, COMT, other variants. We actually have a pretty good set worth analyzing that are pretty well-characterized in research, so we don't have to depend on any one particular allele. We have a pretty good set of those that aren't associated with, I don't know, aggression in boardrooms.
EDIT: This in regards to knowing: "We will quickly try and hang men after three violent crimes."