The respondent mills, a registered dealer under the Bihar · Sales Tax Act, 1947 (Act III of 1947), was carrying on business of manufacture and sale of gunny bags, hessian and other jute products at Katihar. During the period April l, 1950, to March 31, 1951, it sold and despatched its wares worth about Rs. 92,24,386-1-6 to dealers outside the State and realised a sum of Rs. 2,rr,222-9-6 as sales-tax from them. In assessing the , sales-tax payable by the said respondent for-the relevant period the Superintendent of Sales Tax, Purnea, held that the said amount of sales-tax had been realised in contravention of s. r4A of the Act read with r. 19 of the Bihar Sales Tax Rules, and directed its forfeiture under the proviso to that section. The' respondent_ challenged the validity of the said order under Arts. 226 an'Cl 227 of the Constitution. The High Court held that the proviso to s. 14A of the Act was u.ltra 'vires the State Legislature as it violated Arts. 20(1) and 31(2) of the Constitution and set aside the order of forfeiture and quashed the proceedings under s. r4A of the Act. The State of Bihar appealed to this · Court. It was urged by way of preliminary objection on behalf of the respondent that since the proviso to s. l4A of the Act had no application to the facts of the case, there was no occasion to decide its const\tutional validity. The contention of the appellant was that the proviso did apply to the respondent inasmuch