[ianm218]

It’s a literature study on crime deterrence and says the strongest deterrent is how likely criminals perceive apprehension.

I.e. they are much more likely to rob a grocery store if they think they won’t get caught, but the penalty for robbing a grocery store being 1 year or 10 years doesn’t have a strong effect on deterrence.

To your second point - I don’t think it is helpful to find hypothetical holes in their methodology, without reading the individual studies.