Mich. Comp. Laws § 700.3923: Allocation of penalty and interest.

Sec. 3923.

If the probate court finds that it is inequitable to apportion taxes, credits, interest, and penalties in the manner provided in sections 3920 to 3922 because of special circumstances, the court may direct apportionment in the manner it finds equitable.

If the probate court finds that the assessment of penalties and interest assessed in relation to a tax is due to delay caused by the negligence of the fiduciary, the court may charge the fiduciary with the amount of the assessed penalties and interest.

In an action or proceeding to recover from a person interested in the estate the amount of a tax apportioned to the person in accordance with this act, the court's determination in respect to the apportionment is prima facie correct.