There is a lot of law against pot hunting. If the collection includes pots or artifacts that were collected illegally by pot hunters that then sold to brokers that resold, the pots/relics are illegal.
Tony Hillerman the great writer describing the cases of Lt Joe Leaphorn and Sgt Jim Chee of the Navaho Tribal police, has the practice as a theme. For an understanding read his book “A Thief of Time” that recounts the dealings between the pot hunters, professional archaeologists and collectors.
In the southwest there are tens of thousands of archaeological sites that were and are targets for the pot hunters.
For me, Hillerman’s books are travel guides. You read the book and then go visit the places in the far flung crime scenes in Arizona and New Mexico. For a Thief In Time, you can visit the National park at Chaco Canyon, Stay in the actual motel described in Bluff Utah, and take Joe Leaphorn’s float trip down the San Juan River to Mexican Hat. You have lunch where there are some of the best and most extensive petroglyphs in America, across the river from the wash where much of the action occurred.
Any way, to understand this old man and why he may plead innocence but is guilty of buying illegal pots third hand read the book
If you have no reasonable way of knowing that what you are doing is a crime, then ignorance of the law *should* be an excuse.
Unless the “pot” is IDed as to time and place of collection, how can any “crime” be shown, unless the police have proof of date of purchase. There are numerous fakes out there. Proving authenticity is not a simple consideration.
I suspect the Hillerman has quite a bit of fact in his novels, but they are still fiction. I would not rely on them for legal advice. A lot of this law is pretty murky, I am told. Virtually all writers of fiction are prone to “stretch” points to make a plot better.
Something that I have noticed is that the major publishing houses are *very* politically correct, and go so far as to insist on plot changes to fit their political agenda. If authors do not toe the line, they do not get published.