The right of a person to a state annuity, or teacher annuity, or a retirement allowance, to the return of contributions, the state annuity, the teacher annuity or retirement allowance itself, any optional benefit or any other right accrued or accruing to any person under the provisions of this chapter, and the moneys in the various funds created by this chapter, are hereby exempt from any state or municipal tax and exempt from levy and sale, garnishment, attachment, or any other process whatsoever, and shall be unassignable except as in this chapter specifically otherwise provided.
T.C.A. § 49-1558