Indiana Code Title 36. Local Government § 36-7-15.5-10

Sec. 10. (a) A resolution of the commission that establishes an improvement and maintenance district must be approved by the legislative body of the city.

(b) After this approval, the resolution is final and conclusive, and no attack may be made challenging the resolution or the establishment of the improvement and maintenance district, the sufficiency of notice, the existence of the improvement and maintenance district, the public utility and benefit of the proposed improvement and maintenance project, that the benefits equal or exceed the estimated cost or limitation on the assessment levy, the appropriateness of the formula to be used for assessing special benefits and damages, the boundaries of the district, or any other matters before the commission, unless an appeal is taken as provided in section 12 of this chapter.