Yes, you can sue. You are liable for your dog's acts regardless of whether you knew or should have known that your dog was dangerous what the dog does-you must pay for. When the victims sue to get compensation for their damages, it does not matter whether the owners knew their dogs had ever been dangerous before. That means an owner cannot argue in defense that the owner did not know the dog was dangerous, or that the owner took care to prevent the animals from hurting someone. If harm occurs, the owner must pay.