I would not hesitate to call AC. If it works like it does here, they won't tell the owner who called and if they've never been there before, it's unlikely anything serious will happen to the dog or owner. But they will have a record of the dog's behaviour and be able to enforce whatever consequences your local laws allow if the owner doesn't get his act together.

We have a similar issue with a quartet of local dogs. Now they are big, husky mixes so they can and have done plenty of damage to other dogs. I don't know what you have to do to make a husky that mean but they are the nastiest huskies I've ever met. They've completely destroyed everyone else's enjoyment of the trails around here. Their owners keep them leashed, but long flexi leashes. They always claimed that being on-leash meant nothing was their dogs' faults. I've called AC and had long discussions with them about how on-leash and under control are two different things! I know others have called AC too. Last week I was out running and passed these dogs....all on 5 foot leashes and muzzled, which up here means they've all been deemed dangerous dogs! Now maybe the rest of us will be able to let our well behaved, friendly dogs enjoy the trails again!

I've owned a dog who hated every other dog on the planet. Keeping other dogs safe from Kayleigh was my responsiblity. No one else needed to worry that my dog aggressive dog was going to hurt their dog. Protecting other dogs from Kayleigh and her from herself was a ton of work, but it was the only responsible way to keep a dog with that kind of temperment! You shouldn't have to worry about Mikey when you're doing the right things for him!