Can you link or describe the resource you are leaning on here?
I have trouble believing that the massive increase in incarceration rates in the U.S. over the last 30 years is entirely disconnected from the drop in crime rates.
Short version: 76.6% of convicts released from prison are re-arrested within 5 years, half of those within one year. From this we have to add the percentage who committed crimes without being arrested and account for those who would not have re-offended regardless of whether or not they had served prison time. The latter numbers are obviously difficult to come by but I think it's safe to assume that they aren't both zero.
The recidivism rates in countries that use non-prison punishments or shorter prison terms are obviously lower than this (since it would be nearly impossible for them to be any higher).
> I have trouble believing that the massive increase in incarceration rates in the U.S. over the last 30 years is entirely disconnected from the drop in crime rates.
Also, the number of inmates in prison has finally started to decline over the last few years and the crime rate is still falling, consistent with the linked article but not with a link between higher incarceration and lower crime rates.
The jump from recidivism rates to characterizing public safety is a giant flying leap out into a chasm.
That there are places with lesser sentences and lower crime is a good data point for establishing that a society need not rely on imprisonment, but it actually isn't instructive as to the effectiveness of imprisonment in other societies.
I think the US imprisons too many people for too long, but you are using a phrase like 'empirical fact' to describe an opinion you have reached.
Also, note I said "completely disconnected", I'm at least somewhat aware of the speculation and research into lead and criminality (my favorite question is how the lead effect might compare to the Sesame Street effect). An alternate explanation of the trend you speak of in your last paragraph is that stricter enforcement has made criminality less attractive (I'm not endorsing that argument, I'm saying I think it has equal footing with your conclusions).
> The jump from recidivism rates to characterizing public safety is a giant flying leap out into a chasm.
It's a direct corollary to the argument that not convicting them would harm public safety. The assumption made by both is that commission of crimes harms public safety. If that assumption is false then why do we even care about punishing those crimes at all? If they're not hurting anybody then there is no harm in letting them keep doing it and we should just repeal those laws rather than worrying about how well they're enforced.
> That there are places with lesser sentences and lower crime is a good data point for establishing that a society need not rely on imprisonment, but it actually isn't instructive as to the effectiveness of imprisonment in other societies.
The thing about facts is that they're all probabilistic. Nobody knows anything 100%. This is true even in hard sciences but it's especially true in social science. If you want to make the argument that then facts don't actually exist, fine. People are still going to call things facts when they're only mostly sure instead of exactly 100%. And sure, better data is always great. Let's commission some new research. But meanwhile you still have to work with what you have rather than what you would like to have.
> Also, note I said "completely disconnected"
But you're not providing any evidence for your position. Crime rates have gone down everywhere regardless of the presence of "tough on crime" policies. The recidivism rate is so abominable that doing nothing instead would at worst not significantly affect it (because it can't get much worse) and with nontrivial probability would reduce it.
> I'm at least somewhat aware of the speculation and research into lead and criminality (my favorite question is how the lead effect might compare to the Sesame Street effect)
The article goes into this. Lead was banned in different localities and countries at different times and the crime rates in each place matches the lead level in that place in the preceding decades better than it matches anything else proposed as an alternative.
> An alternate explanation of the trend you speak of in your last paragraph is that stricter enforcement has made criminality less attractive
The clearance rate has been essentially unchanged since 1995 (the oldest date available). Moreover, a primary cause of the recent reduction in prison population has been imposing shorter sentences. Meanwhile the crime rate continues to fall.
I have trouble believing that the massive increase in incarceration rates in the U.S. over the last 30 years is entirely disconnected from the drop in crime rates.