The story - not well-written - does indicate there may have been reason to fear the dog. History seems a bit tainted. Very unclear, though.
If a person acts in an aggressive manner or is afraid, the dog will sense it. If you have had German shepherds, you KNOW this.
Therefore, it stands to reason that if an animal control officer (or ANY “official”) is confronted by a “vicious” dog, one needs to try to discern the reason for the dog’s actions.
If the dog is afraid, for whatever reason, it will go into alert/attack mode, and at that point, the choice is to shoot it, preferably with a tranquilizer. Bullets are *ahem* overkill when it comes to dogs in stressful situations.