You specified western Hemisphere, which includes only the eastmost edge of Europe, but still leaves (half) of the UK, France and also Canada and Ireland. US police is hardly going to beat those on many positive metrics.
Odd choice of geographic region for such a comparison in any case.
The latter is like competing with your college football team against a selection of mostly primary schoolers and declaring you're doing fine.
That's just not an aspirational goal or useful comparison.
The punishments can vary so much.
Private prisons create this profit incentive to jail more people.
Prisions should be a cost center not a profit center.
I wholeheartedly agree that 6% of the prison population (128,063 people!) is a situation worthwhile of positive change. But I remain skeptical that it's those damn private prisons that are ruining everything. Mostly I think it's debacles like the drug war that need real immediate attention and change before things will significantly improve.
[0]https://www.pewresearch.org/fact-tank/2017/04/11/u-s-private...
[1]https://www.bjs.gov/content/keystatistics/csv/Total_correcti...
[2]https://www.criminaljusticeprograms.com/articles/private-pri... again citing the BJS.