1. - Special Appeal No. 837 of 1993 arises from the judgment dated January 19, 1993, of the learned single judge on a writ petition. The writ petition was made absolute and the Revenue is in appeal. In D.B. Writ Petition No. 1503 of 1995, the assessee challenged the constitutional validity of Section 143(1A) of the Income-tax Act, 1961 (for short "the I. T. Act").

2. The writ petitioner-assessee had returned a net loss. After adjustments had been made by the taxing authorities under the provisions of Section 143(1)(a) the assessment of loss stood reduced. The taxing authorities under the provisions of Section 143(1A) sought to levy additional tax upon the assessee in this behalf and this was challenged in the writ petition.

3. Section 143(1)(a), (1A) of the Income-tax Act (retrospectively amended in 1993) reads as under:

"143.(1) (a) Where a return has been made under Section 139, or in response to a notice under Sub-section (1) of Section 142,-

(i) if any tax or interest is found due on the basis of such return, after adjustment of any tax deducted at source, any advance tax paid and any amount paid otherwise by way of tax or interest, then, without prejudice to the provision