What do you do when you have a person that you would like to create a biographical record but for what ever reason they do not want or cannot participate?
This is an example from the Minnesota Historical Society on the first woman police officer, Carolen Bailey.
First of all, you be respectful of individual rights of privacy. If you subject is a family member or someone close to you and really does not want their photo, voice or likeness publicly presented then you should probably not proceed.
With public and historical figures you have a bit a leeway but again, the respect thing can help keep you out of trouble.
I guess you will have to decide if this is a personal, public, journalistic or historical creation. Each one of those types of oral histories have to be approached differently.