In CT, you have local police officers, and then the CSP. The CSP will cover where you don't have a local police force.
For decades, every time you purchase a weapon, the paperwork with the information is filed with the CSP. You can sell long guns privately, but pistol sales have to go through a paperwork process.
Remember, they were given choices too. Register, Sell, or Transfer out of State. Since they are going to use the registration forms, how do they know the rifle is still there? Or magazines?
I still believe that the upper levels of the CT government, and the CSP, are just hard headed enough to pursue action.