There is a imunity to a person chargeable with tax in cases of fraud/suppression of facts/ willful misstatement,  :

Is there any imunity to a person chargeable with tax in cases of fraud/suppression of facts/ willful misstatement, who pays the amount of demand along-with interest before issue of notice?

Ans. Yes. Person chargeable with tax, shall have an option to pay the amount of tax along with interest and penalty equal to 15% percent of the tax involved, as ascertained either on his own or ascertained by the proper officer, and on such payment, no notice shall be issued with respect to the tax so paid. {sec. 74(6)}