It is more likely that you will face a vicious dog than you will a vicious human. Those are just the realities of life. The trouble is, if you dispatch a vicious dog, you run the risk of being attacked again. Animal lovers, none of whom were at the scene of the incident, will likely tear into you with as much ferocity as the dog.
With that in mind, you need to be able to articulate the same level of danger as you would for an attack by humans. If you feel you are in real danger, don’t hesitate—but when dealing with a dog you might want to use an alternate weapon, like pepper spray, if you can.
Into the Fray, Episode 19: What About Dogs?
The rules of deadly force still apply when the threat is a vicious dog. You have to be able to articulate that you were in immediate danger of death or great bodily harm. If you CAN’T do that…you cannot draw your firearm to dispatch the threat.
Don’t shoot the dog…unless you are forced to. Dealing with a vicious dog is dangerous in two ways. The dog might get hold of you and dog lovers certainly will come after you. Be ready for both.