equal protection in taxation

The constitutional prohibition applies only to taxation which in fact bears unequally on persons or property of the same class and that mere differences in modes of assessment do not deny equal protection unless they are shown to produce such inequality. Nor does the equal protection clause prohibit inequality in taxation which results from mere mistake or error in judgment of tax officials, or which is not shown to be the result of intentional or systematic undervaluation of some but not all of the taxed property in a single class.