JUDGMENT AND ORDER : Hrishikesh Roy, J. Heard the learned counsel for the petitioners Mr. A. Kakati and Mr. A. Goyal respectively. Also heard Mr. A.B. Choudhury, the learned Sr. counsel appearing for the Guwahati Municipal Corporation (GMC). The respondent No.1 is represented by Mr. B. Talukdar, the learned Govt. advocate. 2. Since common issues are raised and the cases are analogously heard, the following order will dispose of all three cases. 3. The petitioners challenge the respective notice of demand for payment of advertisement tax on hoardings, billboards and glow signs put up by the petitioners in their respective business premises. The petitioners contend that they are exempted from payment of advertisement tax under clause (b) and (c) of Section 173(1) of the Guwahati Municipal Corporation Act, 1971 (hereinafter referred to as the “GMC Act”). While tax on advertisement is leviable under Section 173, when the displayed advertisement is exhibited in the windows of the business premises and the display relate to the trade, profession or business carried out in that premises, advertisement tax is exempted for such displays, under proviso to Section 173 of the GMC Act. 4. Since demand of tax should normally be preceded by an exercise of assessment, the petitioners contend that the tax demand without assessment is wholly without jurisdiction and the same should therefore be quashed. 5. On the other hand, Mr. A.B. Choudhury, the learned Sr. counsel appearing for the GMC submits that the petitioners can approach the appellate forum either under Section 204 or under Section 438 of the GMC Act and entertainment of the writ petition when alternate remedy is available, would not be justified. 6. The power of the High Court to issue writs under Article 226 of the Constitution is limited only by self-imposed restrictions in those cases where an effective and efficacious remedy is available. But existence of alternate remedy do not operate as an absolute bar to entertainment of writ petitions. It was held by the Apex Court in Whirlpoor Corporation Vs. Registrar of Trade Marks reported in (1998)8 SCC 1 , that interference by writ Court is permissible where the impugned exercise is wholly without jurisdiction. In the present cases, the petitioners were not afforded any opportunity before the advertisement tax was demanded from them and moreover no exercise to assess the tax was undertaken with participation of the petitioners. Registrar of Trade Marks reported in (1998)8 SCC 1 , that interference by writ Court is permissible where the impugned exercise is wholly without jurisdiction. In the present cases, the petitioners were not afforded any opportunity before the advertisement tax was demanded from them and moreover no exercise to assess the tax was undertaken with participation of the petitioners. In such circumstances, to reject the writ petitions after so many years would not in my view be justified and accordingly the merit of the cases is being examined hereinafter. 7. The Municipal Corporation is empowered to levy tax on advertisement under Section 144(1)(d) of the GMC Act and the 3rd schedule to the Act prescribes the rate at which, advertisements are to be taxed. While every displayed advertisement can be taxed by the Corporation, exemption is provided for the displays within the window of a commercial establishment, if the advertisement relates to the trade/profession or business carried on within that building. 8. In the present cases, the concerned displays were in the Pantaloon and Big Bazar malls and also in the billboards of the outlets dealing with products of M/s Reliance Telecom Ltd. The content of these advertisements are not of any unrelated product/service but is intrinsically connected with the business carried out in the concerned malls/retail outlets. Therefore such displays/advertisements are clearly exempted from levy of advertisement tax under the proviso to Section 173 of the GMC Act. 9. Moreover the GMC issued the tax demand notice without affording any opportunity to the petitioners or without an assessment exercise where the petitioners could have participated. Therefore, the petitioners had no opportunity to point out that the concerned displays/billboards are exempted under clause (b) and (c) to Section 173 of the GMC Act. 10. The existence of a valid assessment order for raising a demand for tax could have served two objectives namely an opportunity of hearing to the petitioners in the assessment exercise and secondly it would have facilitated the authorities to decide whether the concerned displays/billboards should be exempted under the proviso to Section 173 of the GMC Act. 10. The existence of a valid assessment order for raising a demand for tax could have served two objectives namely an opportunity of hearing to the petitioners in the assessment exercise and secondly it would have facilitated the authorities to decide whether the concerned displays/billboards should be exempted under the proviso to Section 173 of the GMC Act. But in these cases, the Corporation straightway proceeded to recover the advertisement tax by quantifying the due amount in the demand notices and this in my opinion could not have been done because exemption is envisaged to certain categories of displays/billboards, under the proviso to Section 173 of the GMC Act. 11. In the above circumstances, the impugned notices of demand of advertisement tax issued by the GMC in respect of the displays/billboards in the business premises of the petitioners are found to be legally unsustainable and the same are accordingly quashed. 12. However, the above order will not foreclose the option of the GMC to determine afresh on the tax ability of the displays/billboards in the premises of the petitioners. But such exercise must not be undertaken without affording an opportunity to the petitioners to have their say against the proposed levy. The writ petitions therefore stand allowed with this liberty to the GMC by quashing the notices impugned in these cases. It is ordered accordingly.