Putting aside the politics of this… If you want to point to a single factor as having / not having an effect between 2 groups you need to account for other fac

Putting aside the politics of this… If you want to point to a single factor as having / not having an effect between 2 groups you need to account for other factors. You could setup a statistical model. So to be clear, the fact that policemen in the US/UK do/don’t carry guns and have higher/lower crime rate doesn’t prove anything on its own.