Assessee-company filed its return of income declaring nil income, having adjusted interest earned on bank deposits against project/pre-operative expenses-Returns were processed under Section 143(1). Subsequently, AO issued notice under Section 148 to reopen assessment and treated amounts deposited in bank as surplus, and proposed to tax interest as income from other sources, stating business had not commenced and deposits were not directly linked to acquisition of technical know-how, On appeal, CIT(A) allowed assessee’s appeal and concluded that reassessment was initiated on a mere change of opinion of a completed assessment. On Revenue’s appeal, Tribunal held that reassessment was validly assumed, observing that earlier processing was under Section 143(1) and that escapement of income was sufficient under Section 147, and proceeded on merits to treat interest as income from other sources by setting aside CIT(A)’s order. Court held that in view of the conceptual difference between Section 143(1) and Section 143(3), when no order under the latter provision has been passed, AO was not precluded from re-opening assessment, provided he had reasons to believe income had escaped assessment. Court also held that the  Tribunal possesses ample power to decide any issue going to the root of the subject matter Assessee’s objection that the Tribunal could not have taken upon itself to decide it was not tenable   (AY. 1993-94, 1994-95)