Thank you for your question and I'm sorry to hear about this very unfortunate incident.
In Washington, the law provides that the owner of a dog is strictly liable for any damage caused by the dog. This means you have a right to recover the value of your lost dog and any veterinary bills you paid because of the injuries from the dangerous dog's attack. You may sue your neighbor for this amount in small claims
court if the neighbor refuses to pay after you have made a demand.
A dangerous dog is defined by law as follows:
16.08.070. Dangerous dogs and related definitions
Unless the context clearly requires otherwise, the definitions in this section apply throughout RCW 16.08.070 through 16.08.100.
(1) "Potentially dangerous dog" means any dog that when unprovoked: (a) Inflicts bites on a human or a domestic animal either on public or private property, or (b) chases or approaches a person upon the streets, sidewalks, or any public grounds in a menacing fashion or apparent attitude of attack, or any dog with a known propensity, tendency, or disposition to attack unprovoked, to cause injury, or to cause injury or otherwise to threaten the safety of humans or domestic animals.
(2) "Dangerous dog" means any dog that (a) inflicts severe injury on a human being without provocation on public or private property, (b) kills a domestic animal without provocation while the dog is off the owner's property, or (c) has been previously found to be potentially dangerous because of injury inflicted on a human, the owner having received notice of such and the dog again aggressively bites, attacks, or endangers the safety of humans.
Thus, the fact that the dog has killed your dog while it was on its chain on your neighbors property does not automatically make it a dangerous dog under the law. You may be able to obtain the designation by proving that the dog runs at you aggressively if you walk by on the sidewalk.
You would need to report this to the animal control department in your city and request that the dog be designated as a dangerous dog.
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