Sec. 5.6. (a) The general assembly covenants with the purchasers of any bonds issued pursuant to the authority of this chapter that the taxes providing the amounts to be distributed to the district from the electric rail service fund (IC 8-3-1.5-20.6) and the commuter rail service fund (IC 8-3-1.5-20.5), which amounts are pledged to the payment of those bonds, shall not be repealed, amended, or altered in any manner that would adversely affect the levy and collection of those taxes, or change the method of fixing the rates of those taxes, so long as the principal of, or interest on, any such bonds is unpaid.
(b) The board, on behalf of the state and the district, is hereby authorized to make a similar pledge or covenant in any agreement with the purchasers of any bonds issued pursuant to the authority of this chapter.
(c) For purposes of this section, the principal of or interest on bonds or notes shall be considered paid if provision has been made for their payment in such a manner that the bonds or notes are not considered to be outstanding under the provisions of the resolution or trust agreement pursuant to which the bonds or notes are issued.