I do see the implication, and it kinda makes me proud. I guess it naturally follows from being an atheist, an atheist needs to be more rational to deal with the insanity of theist claims, rational people are less likely to commit crimes, therefore there are less atheists in prisons. This is not very far fetched really 
One a side note, evolution does provides a great argument for our morality, and that is the argument I like to use

One a side note, evolution does provides a great argument for our morality, and that is the argument I like to use
