They had tied its leash to a railing. It was bound.

I think you should give your dog a bit more credit:) Though I agree, it depends very much on the dog's upbringing, gender and,(that's just my opinion) their personal history. I am owned by two german shepherds, both rescues. The older one, a male, which I've had the chance to raise as a puppy, is fearless, and fiercely protective of me. The other is a girl, she went through a lot of trauma before we found each other, and well, she's a total wussie. I never even tried to train either of them for protection, but I'm still not convinced that she wouldn't try to protect me - I'm just glad we haven't been tested, and hope we never would.
Do.Or do not.There is no try.

My dog loves me - I am the centre of his universe. However, were I being beaten to death and my assailant offered him a treat, he would wag his tail and go home with the assailant.
Having said that, he's a chocolate labrador and not an alsatian. But each dog is different, and this alsatian has obviously not been trained to be an attack dog. It depends on their upbringing - Jodie's dog here seemed to be quite a meek dog, despite his breed.
I'm a Prick With a Fork.

Not necessarily. If dogs were inherently prone to doing that then why are any dogs held "captive" by neglectful or abusive people or when dogs are dognapped why wouldn't they just attack and go home? It doesn't really work that way. It depends on the dog.
"It's Minnie Pearl's murder weapon."