Section 151 of Income Tax Act "Sanction for issue of notice Other provisions"
151. (1) No notice shall be issued under section 148 by
an Assessing Officer, after the expiry of a period of four
years from the end of the relevant assessment year, unless
the Principal Chief Commissioner or Chief Commissioner or
Principal Commissioner or Commissioner is satisfied, on the
reasons recorded by the Assessing Officer, that it is a fit
case for the issue of such notice.
(2) In a case other than a case falling under sub-section
(1), no notice shall be issued under section 148 by an
Assessing Officer, who is below the rank of Joint
Commissioner, unless the Joint Commissioner is satisfied, on
the reasons recorded by such Assessing Officer, that it is a
fit case for the issue of such notice.
(3) For the purposes of sub-section (1) and sub-section (2),
the Principal Chief Commissioner or the Chief Commissioner
or the Principal Commissioner or the Commissioner or the
Joint Commissioner, as the case may be, being satisfied on
the reasons recorded by the Assessing Officer about fitness
of a case for the issue of notice under section 148, need
not issue such notice himself.
Section 152. (1) In an assessment, reassessment or recomputation made under section 147, the tax shall be chargeable at the rate or rates at which it would have been charged had the income not escaped assessment.
(2) Where an assessment is reopened under section 147, the assessee may, if he has not impugned any part of the original assessment order for that year either under sections 246 to 248 or under section 264, claim that the proceedings under section 147 shall be dropped on his showing that he had been assessed on an amount or to a sum not lower than what he would be rightly liable for even if the income alleged to have escaped assessment had been taken into account, or the assessment or computation had been properly made :
Provided that in so doing he shall not be entitled to reopen matters concluded by an order under section 154, 155, 260, 262, or 263.