(1) If any part of a deficiency is due to negligence or intentional disregard of rules and regulations prescribed by or under this chapter, but without intent to defraud, there shall be added to the tax as a penalty an amount equal to 10 percent of the deficiency.
(2) If any part of a deficiency is due to fraud, there shall be added to the tax as a penalty, in lieu of the penalty under subsection (1), an amount equal to 100 percent of the deficiency.
(3) For purposes of this section, the amount shown as tax by the taxpayer upon a return shall be taken into account in determining the amount of the deficiency only if such return was filed on or before the last day prescribed by law for the filing of such return, including any extensions of the time for such filing.
