Ind. Code § 36-10-9-14
(a) The Indiana general assembly covenants with the purchasers of any bonds or notes issued under this chapter that:
(2) it will not reduce the rates or amounts of those taxes;
as long as the principal of, or interest on, any bonds or notes is unpaid.
(c) For purposes of this section, the principal of or interest on bonds or notes is 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 resolution, ordinance, or trust agreement under which the bonds or notes are issued.
As added by Acts 1982, P.L.77, SEC.28.