I prefer to only get the government involved when I'm unable to resolve the issue with the owners. If they're unwilling to work something out that's what the government is for. Protecting your coop is your responsibility, but an encroaching dog from neighbors shouldn't require you to fork out extra money when it's their responsibility. I've dealt with an aggressive neighbor dog and I told them twice, the second time I had my phone out with the number ready to go. They fixed the issue after I left their porch. Later that year the city forced them to give up the dog because of mistreatment. Luckily I moved away from that crap.