Does the joint return have an understatement of tax or an underpayment of tax?
Understatement or Underpayment An understatement of tax is reporting that you owe less tax than actually should have been reported. There has to be some bona fide understatement of tax on the joint return that was filed. This amount must be real and determinable in amount. This amount must be attributable to some erroneous item or items on the return by the other spouse. Innocent oversights and harmless errors do not count.
