This happened to me 26 years ago. I'm not proud of what I had to do.
But I couldn't put my family or my pets at risk.
We lived in the country, our property backed up to vineyards, animals would be abandoned along the road we lived on. Our cat, Oliver, let us be his family, our dog, Jasper, allowed Oliver into the house after Oliver kicked his butt! Nuff Said!
I walked to my truck, and there was a pup being choaked by a tight collar, it allowed me to release the collar and then ran from me. That evening when I came home, my wife said that the dog would growl at her and be aggresive toward our dog, cat, and child! I called Animal Control and was told that there would be an officer there ASAP. Well...ASAP turned into 3 days later.
I tried to make the dog feel comfortable, offered food and soothing words, it snarled at me and backed away. I called Animal Control Again. They 'claimed' they had sent an agent, and he couldn't find the offender.
Two more reports to Animal Control in the next week and the dog was still terrorizing my family with no response from Animal Control.
I told them that I would take care of the 'problem' with my rifle.
They told me that I could be prosecuted for animal cruelty.
I told them I would counter with negligence since my family was threatened.
The next morning I walked out of my house with my rifle, the dog growled at me and skulked away and watched me, I chambered a round, drew down , and put a bullet right between its' eyes, it never knew what hit it.
I put the carcass in a garbage bag and took it to animal control, placed it on their counter, identified myself by name and address and told them to get rid of it.
They told me that they weren't able to dispose of animals, that I needed to go somewhere else.
I said "Fine!, grabbed the bag and threw it into the dumpster behind the building
I'm not proud of that, I had to protect my family.