If any street gang had a nationwide campaign to shoot house dogs, and was doing so on a daily basis, it would be a top story on the news for months.
When government employees do it?
Covered locally.
Mostly national silence (except on the Internet, where free conservatives can put 2 & 2 together, to the disgust of government employees everywhere).
However, if another legal gun owner were to use his gun because he "feared for his safety" (see George Zimmerman), then there are calls for gun confiscation.
Yes, police officers are asked to put themselves into dangerous situations, but they do not have a univeral right to use the guns they are issued, just because of some supposed fear of a domesticated family pet that meter readers or letter carriers also face each day with no incidents whatsoever.
-PJ