You do realize that law enforcement can lawfully inquire, they simply cannot force you to comply without a warrant, right? Nothing says they can't ring your doorbell and ask you something. Its up to you if you want to respond, or tell them to go fuck themselves. I'm inclined to tell them to fuck right off, and then keep fucking right off to the nearest cliff. But this isn't unlawful for them. Better off to not make a multiple purchase of handguns or if your state has the rifle restriction, that too. Then they don't have forms to fuck with you about.