Indiana Code Title 14. Natural and Cultural Resources § 14-27-3-4

Sec. 4. The collection of assessments is not defeated by reason of a defect in the proceeding occurring before the judgment of the court approving and confirming the assessment of benefits and damages and ordering the work established if the court had jurisdiction.  The judgment is conclusive that all prior proceedings were regular and according to law.  A person may not, at any stage of the proceedings, take advantage of an error, a defect, or an informality that does not directly affect the person.  If the court releases a person of liability or modifies the person's assessment, the act of the court does not affect the rights or liabilities of any other person.