My employer has admitted to a pay equity error. My department head informed me of a pay equity error which entitled me to a substantial raise over a year ago. I should have received 3 times what I actually got. Although, they admitted to the error, I will not be receiving the back pay. They informed me that I would begin receiving the increase immediately but would not be compensated for the lost wages. Have they violated any TN labor laws by disallowing the back pay?

Was the error based on any law? Or was it just a clerical or other internal policy problem? And did the employer do this on their own or was it a result of a complaint you filed with an outside regulatory agency?

No the error was not based on a law. It was an internal error. I was not aware of it until they admitted to the mistake. I have not filed a complaint with a regulatory agency. I am trying to find out if I have grounds to file a complaint with a regulatory agency for the back pay.

Under the circumstances you describe, back pay is optional on the employer's part, not mandatory. No laws have been violated by their refusal to pay back pay.