I'm not aware of any need for written authorization. We have the USA Patriot Act notification prominently displayed, as well as the desk signs that advise that we check each account with Chexsystems. We also do get a signature with regards our obligation to verify customer identity, but it does not specifically say we're going to run ChexSystems.
I hear and I forget. I see and I remember. I do and I understand.--Confucius