Income Tax Act, 1961: s.147 - Power to reassess - The word "opinion" inserted in s.147 after the enactment of Direct Tax Laws (Amendment) Act, 1987 i.e. prior to 1st April, 1989, vested arbitrary powers in the Assessing Officer to reopen past assessments on mere change of opinion - The concept of "change of opinion" stood obliterated with effect from 1st April, D 1989, i.e. after substitution of s.147 of the Act by Direct Tax Laws (Amendment) Act, 1989-Direct Tax Laws (Amendment) Act, 1987 - Circular No.549 dated 31st October, 1989.