It's catch22. Darned if you do and darned if you don't. I believe in most ordinances you are allowed to kill for the safety of your property and chickens are considered property. My daughter's property is in a wooded area and you can bet her DH would shoot a charging Coyote or attacking Raccoon. We don't like to kill wildlife but if it's them or me I know what I'd do. Also they can be rabid - Long Beach, CA found a skunk last week that tested positive for rabies - their first case in the last 35 years.
A Buck headed right into my car at dusk when I had my headlights on. It rammed so hard into the front grill that the grill fell off. I reported the incident to the insurance company and wondered if there was some law about accidents involving wildlife. The police were not concerned and said wildlife is not considered someone's property so therefore there's no liability. That was 18 years ago so don't know what laws say today.