As told to me by a professional dog trainer, Goldens are bird dogs, they instinctively retrieve birds in their mouth without biting them. They are difficult to train to bite anything and when they do they don't usually use much force more of a warning. They can be trained as alert dogs and act aggressive but near impossible to train them to be protection dogs other than to alert.
I've got a Border Collie, my first one, and in play I can get him worked into a frenzy where he'll strike but with no pressure to his bite. It's like it is impossible for him to actually bite down. I think it's been bred out of them as they're sheep dogs and you wouldn't want them to damage the product.
I don't have a problem with the cops shooting a dog that is really a threat, but it seems that in a lot of these cases it isn't necessary to use a gun as the first option. At 13, I was a paperboy in Alaska where they keep dogs big enough to drive off the bears. I had to deal with quite a number of aggressive dogs on my route but I never needed to shoot one.