This is obviously a tragic situation but the Rottie did not cause the problem. I know it had to be a horrible shock for the cop to see this happen but cops are taught to act responsibly under stress and I would not call pulling out a gun and shooting the Rottie "responsible"
When you have cats in the home you have to be aware of where they are when you open the door to go in or out. The Rottie was an innocent victim. You can bet I wouldbe looking for the best attorney in town.......can't imagine losing my Rottie like this.
:(