The following table provides the laws concerning the transport of horses in vehicles. On July 5, 2008, Rhode Island became the sixth state to ban the use of double-deck trailers to transport horses by law. PA, NY, MA, VT, and MD previously banned the use of double-deck (or "possum belly") trailers by statute. Two states, CT and VA, regulate their use by administrative regulation. Arizona and California ban the use of double-deck trailers for the transportation of horses to slaughtering establishments.
According to the advocacy group, the Equine Protection Network (EPN), accidents involving double-deck horse trailers in three states in recent years resulted in the deaths of 55 horses. These advocates contend that the use of double-deck trailers is dangerous because the trailers are not "designed, safety tested, or manufactured for horses." See the EPN at http://www.equineprotectionnetwork.com/.
Penalties for violating laws prohibiting the use of double-deck trailers varies by state. For example, in Maryland, a first violation results in a $500 penalty per horse; subsequent violations incur a $1000 penalty per horse. Likewise, Rhode Island also provides for a first penalty of at least $500 per horse, and at least a $1,000 for each subsequent violation. Under Pennsylvania's law enacted in 2001, each violation constitutes a misdemeanor in the third degree for each horse transported in such fashion.