Concluding that characterizations in the Internal Revenue Code (IRC) are not dispositive in the bankruptcy context, the Court held that the exaction imposed by § 4971(a) of the IRC on the amount of an accumulated funding deficiency of a pension plan was a penalty, and not an excise tax entitled to seventh priority under § 507(a)(7)(E). The Court found that the exaction imposed by § 4971(a) was imposed for violating a separate federal statute (ERISA) that requires the funding of pension plans, and had an "obviously penal character." Accordingly, the Government's § 4971(a) claim was to be dealt with as an ordinary, unsecured claim in the plan. However, the Court concluded that the Government's § 4971(a) claim could not be subordinated to those of other general unsecured creditors because the "categorical reordering of priorities that takes place at the legislative level of consideration is beyond the scope of judicial authority to order equitable subordination under § 510(c)."