One just needs to read the news. It has been going on for decades.
https://www.seattletimes.com/nation-world/border-indian-reservations-sources-of-drug-smuggling/
https://www.politico.com/magazine/story/2018/07/01/akwesasne-american-indian-community-218936/
The border tribes smuggle it across and the gangsters drive it from route to route through reservations.
Well then, do something about it!
Don't even need to read. Watch, listen, and learn.
Poorest Native American Reservation (by Peter Santenello)
Neighbor, who died a few years ago, was 1/4 Indian, had an almost religious devotion to local tribe that lived on the nearby “Rez:”
He was a counselor at alcoholism clinic, made good money helping people get sober. He’d be furious but not surprised about drug-smuggling situation. That’s what Indians do because they can. Needs a change of laws, which isn’t going to happen.