The history of the "one bite rule"

"Rules imposing liability for harm caused by domestic animals find their origin in authority no less ancient than the Pentateuch." Wilson v. Simmons, 103 S.W.3d 211 (Mo.App. W.D. 2003).

The one free bite rule was the law of England on July 4, 1776. Therefore it became the law of the US states at that time. Because it was part of the "common law" (meaning the judge-made law of England), it was not put into the state codes. The various pronouncements of the law had to be located in the law books of England going back to the 1600s.

The best expression of the rule is found in Restatement (Second) of Torts, § 509:

• "(1)  A possessor of a domestic animal that he knows or has reason to know has dangerous propensities abnormal to its class, is subject to liability for harm done by the animal to another, although he has exercised the utmost care to prevent it from doing the harm.
• "(2)  This liability is limited to harm that results from the abnormally dangerous propensity of which the possessor knows or has reason to know."

As stated in the prior section, most American states have either eliminated or modified the one bite rule. The list of "one bite states" is in Legal Rights of Dog Bite Victims in the USA. That web page also has a list of the states that have adopted state law strict liability. The United Kingdom, by the way, still relies upon the "one bite" rule (see the Animals Act 1971, section 2, subsection 2).

If you are in a state that has the one bite rule, you need to research it first by reading Legal Rights of Dog Bite Victims in the USA, and then (if that section of Dog Bite Law is insufficient or silent about your state) in the case books of your state. Because legal research requires training, non-lawyers who have a claim or must defend a claim are strongly advised to see an attorney rather than attempt to research this issue.