My question involves defamation in the state of: California

I am an assistant manager of a large retailer in california. This week I was accused by the store manager of kicking a customer out of the store and refusing service. I absolutely denied the accusation but was required to go to the managers office and review video tapes of my actions that night to prove my innocence which was proven. I feel he questioned my integrity, honesty and improperly required me to view video tapes of MYSELF.

Any thoughts?