My a dep sheriff took in his after he was retired. He said some of the drug ones will sometimes form a dependence if the find a large stash and manage to get into it. Worse with coke then other stuff I guess because the dust is more transportable in the air.
That’s my theory. The dog became addicted.
Sniffing dope all the time cannot be a good thing.
What do they use to teach them to sniff dope?
Now THAT is an interesting idea.