Prior to his death in 1988, Steve J. Pilafas executed a will and a revocable inter vivos trust which he subsequently updated on two occasions. Steve funded the trust during his lifetime with assets that included a residence and other real property as well as interest in a promissory note and deed of trust on a mobile home park. The terms of the trust provided that Steve could revoke the trust during his lifetime only by delivering an “instrument in writing” to the trustee. When his son, James S. Pilafas (defendant), conducted a diligent search of Steve’s home and belongings for the original will and trust documents, he found neither. Parties challenging enforcement of the will and trust (plaintiffs) asserted that the will and trust were revoked pursuant to the common law presumption that a testator revoked his will if the will was last seen in the testator’s possession and is missing from his belongings after his death. In support of their position, they offered evidence showing that the drafting attorney turned over the final documents to Steve, that a diligent search of the house was unsuccessful and that Steve had been meticulous about keeping track of important documents. James Pilafas and other proponents of the will and trust argued that the presumption did not arise because insufficient evidence was presented at trial to show that the will was last seen in Steve’s possession and that it could not be found after his death. The trial court determined that Steve had revoked his will and accordingly died intestate. James Pilafas and the other proponents of the will and trust appealed to the Arizona Court of Appeals.