I did catch that tidbit on another thread. My comment there is that Vang being a landowner means he understands what ownership is, therefore he must be familar with the concept of trespass.
Frankly, I don't care what use other people had for his property, in season or out. I'd like to know if this "probable" serial killer used it for practice, or possibly for psychotic play-acting with others of his ilk.
In fact, I'd like to know who assisted him in preparing his defense ~ which was quite clearly prepared long beforehand.
The victims' only mistake was in being too trusting of an armed man. It wasn't their knowledge of the intricacies and subtleties of the law that got them into trouble.