An estate must go through the formal probate procedure when: The decedent did not reside in New Mexico There is no valid will The validity of the will is being contested Heirship is unclear Honoring creditor claims or all bequeathments would result in exhausting the estate before all claims are resolved Someone is challenging the appointment of a personal representative or alleging breach of fiduciary There are other issues related to estate holdings or assets transferred into the trust upon death