Actually, unless we can prove causation (not just correlation), we have to assume it is a coincidence.
The fact that such laws did not lead to an increase in crime is a good point to make in an argument. However, the idea that the laws are responsible for a decrease in crime is something we can't prove.
Have to agree that it's like a fingerprint that had reason to be there at the crime scene.
I am just glad that it's more than the other side has.