I work in a resale shop in Columbus, so I can only give you an idea how the Columbus law works.
Customers usually sign a slip stating that the item is theirs and theirs to legally sell, this takes all the liability off the shop. Anything with a serial number must be held for 7 days (this goes into a police database, LEEDS program.) Beyond that 7 day period, for serialized and nonserialized items, if it is a stolen item and the police recover it then the shop takes the loss and has to pursue charges themselves, not the owner.
Every fucking day I get a lovely mix of people, from hillbillies to heroin addicted dublin teenagers selling shit they lifted from cars. I've had people threaten to kill me over $30. Fun business.