1. Gather the decedent's personal details. That I am well acquainted with the above-named decedent and make this affidavit regarding the legal domicile of said.How to write an Affidavit of Domicile? Instructions for Completing Affidavit of Domicile. Complete Form ET-141 if it is claimed that the decedent was not domiciled in New York State at the time of death. A legal document that establishes a person's Residence at the time of their death. Verify the home address of a person who has died. Required Information. Before you begin filling out your form, you need to have the following information on hand: The decedent's full name and date of death. Use our Affidavit of Domicile form to verify the last home address of a deceased person to speed up the inheritance process.