You're right that I'm stating things that are correlated without showing a good argument for causation. But the book that I keep recommending, which (incidentally) is on record as Bill Gates' favorite book, shows multiple lines of evidence including lines that indicate causation.
But if you don't want to be convinced, I won't bother trying to convince you. Because any one line of evidence is easily dismissed and life is too short for me to pursue this topic in full depth.
So far, my original interest in the book from your earlier mention has been reduced by your less-than-stellar use of statistics in making your point. If that's all the book offers, my time is better spent elsewhere.
As for this topic, let me add some more. In interviews with convicted murderers, the most common reason for murder is that they felt wronged and that there was no other form of justice available to them. This is direct evidence that a desire for extrajudicial justice is the top cause of murder.
Murder is not evenly distributed. It is concentrated in places and communities where people feel that they do not have access to the justice system. In the USA that means concentrated in minorities, inner cities, and rural areas. Unsurprisingly, murders are concentrated in the same groups.
This suggests that improving trust in the police should reduce crime. In fact that is the idea behind community policing, and there is evidence suggesting that it really works.
Let's focus on minorities for a second.
From https://www.pewresearch.org/fact-tank/2020/06/03/10-things-w... you can verify that over 80% of blacks believe that the police system is unfair to them. Over 60% of whites agree with that assessment. We had a bunch of protests last year over this issue.
Independent research has verified that the blacks are basically correct. This has lead to consequences including many successful lawsuits that put various police departments under outside control for particularly egregious behavior.
We should therefore predict that blacks should commit murder much more often than whites. And indeed, US blacks commit murder at about 6x the rate that US whites do.
Let's contrast to Germany. Germany does not have a large disenfranchised minority equivalent to US blacks. In fact you can see in https://www.europeansocialsurvey.org/docs/findings/ESS5_topl... that an absolute majority of every socioeconomic group in Germany believe that poor people there are treated fairly by the justice system. Which means that the top reason given by murderers for murder is much less likely to happen in Germany.
So you see, it isn't as simple as saying that both the USA and Germany are law and order systems. A significant minority of Americans believe that they don't have access to law and order. And that portion commits most of our murders. Therefore while we have a justice system and it works pretty well for you and me, inequitable access to justice is still a problem in the USA.
I'm not that interested in what Gates thinks a good book is. Being famous/successful/rich/humanitarian isn't super relevant to being able to identify a good book.
> interviews with convicted murderers
Accumulation of anecdotes != non-anecdotal evidence. It's interesting, but just anecdotal.
> where people feel that they do not have access to the justice system
A statement that is very hard to prove. I don't think you did, and I'm not sure if it's really possible given the general replication crisis within psychology.
> improving trust in the police should reduce crime
I think your evidence is once again insufficient to make the point, but I will agree that the conclusion seems more-or-less valid.
> We should therefore predict that blacks should commit murder much more often than whites.
You don't have to predict that, because it's already well-known. As such, a) you made a trivial prediction, b) you have to show a causal link, c) you have to show that your posited cause is in fact the dominant cause of the effect you're looking at, and d) you have to demonstrate the direction of the causality. You haven't done b, c or d. IIRC, there are a lot of persuasive alternative explanations for the difference in the black/white murder ratio, all of which would have to be addressed. Since I think this explanation of that ratio is much less persuasive than other potential causes, I don't think this point is tenable.
> every socioeconomic group in Germany believe that poor people there are treated fairly by the justice system
That's a really good bit of evidence, and interesting to think about. I will agree with you that as far as "extrajudicial death penalty vs. law and order society" goes, Germany seems decently representative of the latter. However, as I mentioned above, the US side of the comparison is far less apparent: the critical piece of the logic puzzle doesn't work.
After my first reading of your comment, I didn't really expect to find holes in most of the points you made, when I made my response. Thought I'd be agreeing with you more. But here we are. It was definitely interesting. Thanks.
However some of the successes of community policing (particularly when you have neighboring cities, one of which adopts it and another of which doesn't) do suggest a causal link with causality going the right way. Namely that activities on the part of police aimed at increasing trust within problem communities, result in those communities experiencing a decrease in violence and crime.
Yeah, though that just means it's harder to actually find out what's true. That's why the replication crisis in psychological sciences is a crisis. We can't treat gaps in our knowledge like supporting evidence.
> Namely that activities on the part of police aimed at increasing trust within problem communities, result in those communities experiencing a decrease in violence and crime.
That sounds great, and does seem like you're right about that specific item.
You're trying to equate 'extrajudicial death penalties' (and in context, they were revenge-based, not defensive) with gun ownership and self-defense.
You're then equating 'Germans don't really think about using guns for self-defense' with 'a law and order society'.
And then you're trying to say that we can make informed comments about "extrajudicial death penalty vs. law and order society" by looking at "more gun ownership in the US vs. less gun ownership in Germany". It just doesn't compute.
The comparison isn't there. The stats don't fit the argument.