The right of a person to a pension, an annuity, or a retirement allowance, to the return of contributions, any benefit or right accrued or accruing to a person under the provisions of this act and the moneys in the various funds created under this act, shall be exempt from any State or municipal tax and from levy and sale, garnishment, attachment or any other process, and except as in this act otherwise provided, shall be unassignable.
N.J.S. § 43:8A-20