When a decedent, or a person who dies, leaves a will, a proceeding must be completed in the Surrogate's Court to probate or prove the will. Obtaining a letter of administration is one of the first steps an administrator should take when probating a will in New York state.A letter of testamentary is a courtordered document that grants the executor of an estate the authority to manage the deceased person's assets. 6. How Does the Public Administrator First Receive Notice of an Estate? How can I Report a Death to the Public Administrator? These letters are utilized to designate one of the heirs as the estate's administrator, granting them the power to collect and distribute the deceased's assets. Any other documents required in the specific state where the deceased lived. The following is not legal advice, but merely a guide in the process of completing your deceased beneficiary packet. A letter of administration is a courtissued document that gives someone the authority to act as the estate administrator.