Allowing an aggressive dog to dig under a border fence would be a failure to use reasonable care to prevent foreseeable harm, which is negligence. Damages would likely include reasonable veterinary expenses incurred in treating a dog harmed as a result. Unfortunately, human pain and suffering would probably not be recoverable unless there was physical injury to a person. California law does recognize some limited liability for emotional harm to bystanders of a traumatic injury, but whether that would extend to an injury involving a companion animal is a question.
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You can certainly sue for all damages related to treating your chihuahua's injuries and any medical devices it may now need. It is unlikely you can recover for your own pain and suffering.
Contact the CA and your county bar association for referrals.
The foregoing is for general information purposes and does not establish an attorney-client relationship.
I am sorry you saw such a traumatic event and your dog was injured so badly. California law (Civil Code section 3341) does not recognize your emotional trauma from seeing your dog viciously attacked. Were you physically injured by the accident? If so, you may be able to money for your medical treatment, pain and suffering. If so, you may be able to get reimbursed for your out-of-pocket expenses like the veterinarian's bills and medication. Sometimes the dog owner has insurance that will cover the costs. You may also want to take photos of the fence area the dog came through that shows what it looked like on your side of the fence the day your dog was attacked.
It is impossible to give comprehensive legal advice in a public forum no matter how well researched. That is why I only give general legal information in response to this type of public question or comment. Before relying on any information given in response to your question or comment, contact a licensed attorney in your state to discuss your particular situation. I am only licensed to practice law in California.
You can sue for the loss of economic value (i.e., the worth of the dog or loss thereof) but this does not extend to your emotional attachment to your dog in terms of placing an economic value on that attachment. Woof! Hope your pup feels better!
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