[mrsmel]

But why take out your action on other innocent dogs when the human is to blame? The dogs wouldn’t have shot your dog.

[Cboldt]

-- But why take out your action on other innocent dogs when the human is to blame? --

It's tit for tat. You could ask the same question of the cops who shot "your" innocent dog. Not that there is moral justification in tit for tat, but killing livestock is a lesser offense than doing violence against a human.