To prove that you live in California, you must present two documents that contain your California physical address. Write a letter to a state agency, like the DMV, or voter registration, that will require an answer from them.Proof of a physical address is required. Don't have utility bills? Cal. Code Regs. Tit. If you wish to request a DMV certification letter as a proof of residency document, please complete the DMV Certification request form .