In Missouri, you can recover damages related to dog bite injuries on theories of strict liability, premises liability, and/or negligence per se. These cases are proven in different ways. Notably, in the state of Missouri, proving a case under the strict liability theory has usually required that the dog owner have knowledge or constructive knowledge of their dog’s dangerous propensities. However, in August of 2009, the Missouri State Legislature passed a law stating as follows:
The owner or possessor of any dog that bites, without provocation, any person while such person is on public property, or lawfully on private property, including the property of the owner or possessor of the dog, is strictly liable for damages suffered by persons bitten, regardless of the former viciousness of the dog or the owner's or possessor's knowledge of such viciousness.
More and more states, including Missouri, are doing away with “one bite” or “first bite” laws, and are adopting a more rigorous strict liability standard. Under current Missouri dog bite law, when it is proven that an owner was somehow negligent, such as by not properly restraining the animal, the victim may often recover damages without proving the dog’s viciousness.