Dogs are more aggressive when on leash, thats why I try not to use a leash whenever possible. I regularly walk my dog without a leash when it is allowed.
When we saw a bear my dog barked and never left my side and looked to me for guidance, the bear walked back in the woods, My dog is a dutch sheperd which hasn't been destroyed by american breeders as of yet.
I trained police K9 and personnel protection dogs for a few years and have more opinions then I know what to do with, but I get much joy out of watching my dog run free in the widerness, but he enoys it even more, it doesn't really bother me if he chases a deer out of our camp or disapears for a few minutes in the woods, he's a dog and is alot more in tune with whats going on in the woods then I am.

I do always keep him on leash where horses are allowed regardless of laws.