This looks like a situation that has been ongoing for quite a while. The dog was most likely aggravated by an earlier incident. If the boy is really autistic, then there is a possibility that he could have done something to the dog beforehand. It’s hard to get to the truth, but you have to consider the variants of different possibilities if you have the time to.
When the news reporter said the dog is under observation, there is a good chance that it may normally be a very friendly dog. They didn’t say that it was scheduled immediately for neutralization. I can only imagine what the Dog Whisperer is saying about this: “You have to rehabilitate the owner and train the dog”. Many owners don’t even understand their own dogs.
Clearly the dog felt that it needed to protect its owner from a threat. There was no barking involved either so the dog was hunting for the kid outright. The dog had a need to neutralize its threat probably because it felt that it’s owner lost control of the situation. The dog did what it thought best for the situation.
People are trying to apply human psychology to the dog. People are also trying to apply human psychology to the cat. We forget that both animals have paws. They think completely different. We are very shortsighted in how we interpret other animals actions. In fact, we are very out of touch with other animals psychologies today. We want to apply human tendencies to all the animals that we don’t understand.