50. Liability to pay tax in event of breach of condition of exemption. - (1) If any specified class of sales or purchases is exempted under section 49 from the whole or any part of any tax payable under this Act subject to any condition, then in the event of a areas of such condition, in respect of any goods so sold or purchased, the setter or purchaser responsible for such bleach shall notwithstanding anything contained in section 3, be liable to pay tax on such sale or purchase, as the case may be. To the extent to which it was exempted under section 49 from the payment of tax.
(2)If the Commissioner has reason to believe that the seller or purchase, as the case way be, has incurred liability to pay tax under sub-section (1), he shall serve on the seller or purchaser, as the cage may be, a notice requiring him on a date and a place specified therein, either to attend and produce or cause to be produced all evidence on which such person relies in connection with his liability under this section or to produce such evidence as is specified in the notice. On the date specified in the notice, or as soon as may be thereafter, the Commissioner shall, after considering all the evidence which may be produced, assess to the best of his judgment, the amount of tax due from him within a period of not more than four years from the date on which the breach concerned has come to the notice of the Commissioner:Provided that the provisions of all the provisos to sub-section (1) of section 42 shall mutatis- mutandis apply to assessment proceedings under this section.
