1. The petitioners in all these writ petitions are dealers in gold and jewellery, who had opted to pay tax at compounded rates under Section 8(f) of the Kerala Value Added Tax Act, 2003 [for short, 'KVAT Act'] during the assessment year 2011 - 2012. During the year in question, the provisions of Section 8(f) were amended and the issue involved in these writ petitions is with regard to the effect the said amendment had on the option for compounding exercised by the petitioners. It would be apposite, therefore, to first notice the statutory provisions as they stood during the assessment year 2011 - 2012. The provisions of Section 8(f) as they stood on 01.04.2011 were as follows:

“8. Payment of tax at compounded rates:

(f) [(i) any dealer in ornaments or wares or articles of gold, silver or platinum group metals including diamond may at his option, instead of paying tax in respect of such goods in accordance with the provisions of section 6, pay tax at, -

(a) one hundred and fifteen per cent, in case their annual turnover for the above goods for the preceding year was rupees ten lakhs or below;

(b) one hundred and twenty per cent, in case their annual turnover for the above goods for the preceding year was above rupees ten lakhs and up to rupees forty lakhs;

(c) one hundred and thirty five per cent; in case their annual turnover for the above goods for the preceding year was above rupees forty lakhs and up to rupees on crore; and at

(d) one hundred and fifty per cent; in case their annual turnover for the above goods for the preceding year exceeded rupees one crore;

of the highest tax payable by him as conceded in the return or accounts, or tax paid by him under this Act, whichever is higher, for a year during any of the three consecutive years preceding that to which such option relates.;

Explanation 1:- Where a dealer had not transacted any business for the last three years consecutively, the highest tax paid or payable for the year during the year or years he transacted business shall be considered for the above purpose.

Explanation 2:- [Where during any such preceding year, the dealer had not transacted business for any period in that financial year, the tax payable for the twelve months shall be calculated proportionately on the basis of the tax payable or the turnover conceded, as the case may be, for the period during which such dealer had transacted business.;

Explanation 3:- Dealers opting for payment of tax under this clause shall pay compounded tax in respect of all their branches existing in the year to which the option relates.

Explanation 4:- Where a dealer has not opted to pay compounded tax with respect to a new branch opened in 2008-09, the compounded tax payable for such branch for the year 2008-09 shall be notionally fixed as the average of the compounded tax paid for the principal place and branches in that year and if the new branch opened is the first branch, the compounded tax payable for it shall be the same as that payable for the principal place of business.;

Explanation 5:- Where a dealer opens a new branch in the current year, the additional compounded tax payable under this clause in respect of such branch shall be the average of the tax payable by him in respect of his principal place of business and all branches. [xxx]

Explanation 6:- Where a dealer has opted for payment of tax under this clause for the first time in 2010-11 and has commenced business only in 2009-10 and the tax payable as per return or account during 2009-10 is less than the output tax payable, then the tax payable for 2009-10 shall be notionally re-determined on the basis of output tax for determining the tax liability for 2010-11.;

Explanation 7:- Tax payable as conceded in the accounts includes the tax payable on suppressed turnover subsequently detected also.;

Explanation 8:- Where a dealer who had opted and paid tax under this clause during previous years with respect to a branch that had remained closed during the who