YES, a big fat capital YES! Duncan bites. Not me but he would bite a stranger or an intruder in a NY minute. He has bitten people in the past, one guy who was trying to break into our house, he bit him in the hand and the lip, and another friend of my boyfriend's that came into the bedroom where I was sleeping.
He is very over-protective of me and will bit anyone that comes near me if I am sleeping (Even Collin!) or that sneaks up behind me when we are out walking. I have to keep a very close eye on my surroundings when we are out in public. He listens to me but I have to make sure I am telling him what to do and not to panic and try to protect me. He is insecure and nervous around strangers and I have to give him very strong leadership.
It's tough owning a dog like that, let me tell you! It's been a long road with lots of time and money spent!

So those of you who think you want a dog that is protective, think again!!