Preferred database design method for assigning user roles? (Hats vs. Groups)

Question

I have medium sized MySQL database with a primary \"persons\" table which contains basic contact information about every human being connected to the theatre and theatre school

Answer 1

I'm using an ACL package for fine-grained permissions on the site - the heart of my question is more about how to store the metadata for individuals who have different roles and build a few safeguards into the system for data integrity (such that a person must have a teacher record in order to be set as the teacher of a class - the foreign key constraint references the teacher table, not the person table).