Missouri Revised Statutes Title X. Taxation and Revenue § 136.370. Employee error, cause of late return--no penalty to taxpayer, when

Pursuant to chapter 143 and chapter 144, the director shall waive any interest or penalty assessed against any taxpayer when it is determined by the director, the administrative hearing commission, or a court of law that the negligence of an employee of the department resulted in undue delay, as defined by rule or regulation, in either assessing tax or notifying the taxpayer of the liability owed. Such waiver of interest or penalty shall be for that amount attributable to the period of delay and for any time that the penalty or interest is under appeal.