In my day if it was found on your property, you were responsible.

As always, it all depends upon who you know, and who you are. If you're a nobody, or indeed a notorious hippy, you can get hauled off to jail for anything found on your premises, even if it was placed there by the very authorities who so conveniently "found" it. If you're a well-connected big shot, apparently, you can use the "Unclear-Who-Owns-It" defense.

PS ~ isn't this BS?