Some states are “open range” or a “fence out” states, meaning that a livestock owner does not have a legal duty to prevent animals from getting onto the roadway. But some state legislatures have enacted statutes known as "stock laws" that modify the common law (rules contained in court opinions written by judges) and prohibit owners from allowing animals to run at large.
Washington State is not an 'open range' or 'fence out' state. Instead, it has 'stock laws' that require livestock owners to prevent their animals from running at large. Under Revised Code of Washington (RCW) 16.24.010, it is unlawful for any person to permit domestic animals to run at large in this state. This means that livestock owners have a legal duty to fence in their animals and may be liable for damages if their animals trespass on another's property or roam freely. Additionally, specific counties or municipalities within Washington may have their own regulations regarding livestock, which can impose further restrictions or requirements on animal owners.