§ 410. Exemption from taxes and legal process. The right of a person to a pension, a pension-providing-for-increased-take-home-pay, an annuity or a retirement allowance, to the return of contributions, the pensions, the pension-providing-for-increased-take-home-pay, annuity, or retirement allowance itself, any optional benefit, any other right accrued or accruing to any person under the provisions of this chapter and the monies in the various funds continued under this chapter:
1. Are hereby exempt from any state or municipal tax, except the estate tax, and
2. Shall not be subject to execution, garnishment, attachment, or any other process whatsoever, and
3. Shall be unassignable, except as in this chapter specifically provided.