No matter where you're from, motor home and RV accidents in Mexico are subject to the laws of Mexico, not the laws of the United States. In view of the fact that Mexican law considers auto accidents a criminal offense, as well as a civil matter, if you are involved in an auto accident while traveling in Mexico and do not have proper vehicle liability insurance provided by a Mexican insurance company, you may be required to serve time in prison.
To avoid complications and other offenses that are punishable under Mexican law (which can include the impounding of your RV) you must have liability insurance, from a Mexican-licensed company. Typical American and Canadian automobile policies nearly always exclude the special coverage needed for those who drive their motor homes while traveling through Mexico. Specialty motor home policies on the other hand can provide coverage for physical damage to your motor home when traveling into Mexico.
When investigating Mexican insurance, if you choose to purchase a full-coverage Mexican policy (that which exceeds the level of liability required) your U.S. insurance provider may be viewed as secondary to your Mexican policy for any losses that may occur in Mexico. Thus, would then be dealing with the Mexican insurance company in the event of your motor home settlement.
All coverage information and explanations outlined are general and are not representative of all conditions and exclusions. All insurance coverage is dependent on the terms & conditions of the issued policies.