The Board of Tax Appeals was correct in affirming the orders of the Tax Commissioner on authority of the Fifth Third Union Trust Go. case, supra. The equal protection clause of the federal Constitution does not assure uniformity of judicial decisions. The general rule is that a decision of a court of supreme jurisdiction overruling a former decision is retrospective in its operation, and the effect is not that the former was bad law, but that it never was the law. The one'general exception to this rule is where contractual rights have arisen or vested rights have been acquired under the prior decision. The assessment and payment of a tax does not grow out of a contractual relationship, and there is no showing that any rights have become vested in the appellants under such prior decision.

Decision affirmed.