DALIP K. KAPUR, J.

By this writ petition the petitioner sought to challenge the vires of certain provisions of the Delhi Sales Tax Act, 1975. The petitioner being a "registered dealer" for the purpose of the Delhi Sales Tax Act has been directed to pay an amount of Rs. 44,776.82 as interest under section 27(1) of the Act. It may be mentioned that the said amount of interest is due as simple interest in case a registered dealer fails to make the payment required by section 21(3) of the Act. There is no dispute in the present case about the facts of the case, i.e., we are concerned with the quantification of the interest, but with the validity of the provision.

It will be convenient here to refer to section 21 which states that tax has to be paid in the manner prescribed and sub-section (2) provides that every registered dealer and every other dealer who is furnished a notice to file a return of turnover, have to file their returns. It is then that sub-section (3) comes into operation and this provision may conveniently be reproduced. It states :

"Every registered dealer required to furnish returns under sub-section (2) shall pay into a Government treasury or the Reserve Bank of India or in such other manner as may be prescribed, the full amount of tax due from him under this Act according to such return, and shall, where such payment is made into a Government treasury or the Reserve Bank of India, furnish along with the return a receipt from such treasury or bank showing the payment of such amount."

It is this amount which the petitioner failed to pay and it is on this account that interest has been imposed. The provisions of sub-section (1) of section 27 show that interest has to be calculated at the rate of one per cent per month for the first month and one and a half per cent per month for the period during which the default continues, and this interest is continued either till the payment is made or till the assessment is completed under section 23 whichever is earlier. If we read these two sections together, there is a clear provision that a registered dealer, who fails to pay tax according to his return, has to pay interest as calculated by the section. On the other hand, there is no provision requiring non-registered dealers to pay interest. It may be recalled that there is a similar provision regarding payment of interest to be found in the Income-tax Act, 1961, in respect of tax payable according to a return. For example, section 140A requires payment to be made and interest is provided in section 139(8). The provision regarding interest imposed on registered dealers under the Delhi Sales Tax Act seems to be similar.

The question which is raised before us is that the provision is ultra vires because it extends only to registered dealers and does not apply to other dealers. For this purpose, it is again convenient to set out section 21(2) which reads :

"Every registered dealer and every other dealer who may be required so to do by the Commissioner by notice served in the prescribed manner shall furnish such returns of turnover by such dates and to such authority as may be prescribed."

It is contended before us that sub-section (2) equates registered dealers with other dealers who may be required by the Commissioner to file returns. These two sets of persons have to file returns. However, sub-section (3) states that the tax, or rather what may be conveniently called advance tax, is to be paid only by registered dealers and not by those other dealers whom the Commissioner by notice has asked to furnish returns. The learned counsel for the department states that for those persons there is a rule, but for the purpose of this contention we disregard that rule, because it is the vires of the section which is in question.

It appears to us that there is a great difference between a registered dealer and an unregistered dealer under this Act. For instance, a registered dealer has certain advantages which make it obligat