Okay, essplain this to me. If your an illegal alien and your stopped by the authorities in a sanctuary jurisdiction, they will not ask for your papers and will not deport you. The reasoning is, it is a federal statute and the feds need to handle their own issues.
BUT, if I am stopped by the local sheriff in possession of a suppressor, legal in my state, the sheriff will ask me for my papers, and if I don't have any, the suppressor will be confiscated, I will most likely be detained and charged with a federal crime.
Why do local jurisdictions pick and choose which federal laws they will enforce? Dumb question.