The expression "external source" in section 147(b) of the Income-tax Act, 1961 is not restricted to opinions expressed or findings given by Courts of law or the Tribunal or other authorities under the Income-tax Act.

( 1 ) THE following question, which is common to both the assessment years under reference, namely, 1960-61 and 1961 -62, has been referred to this Court by the Income-tax Appellate Tribunal (Delhi Bench a ) (hereinafter referred to as the Tribunal under section 256 (1) of the Income-tax Act, 1961 (hereinafter referred to as the New Act) :-

"whether on the facts and in the circumstances of the case the Tribunal was legally justified in holding that it was a case of mere change of opinion on the same facts and the assessment could not be reopened under section 147 (b) of the Income-tax Act, 1961?"

( 2 ) THE relevant facts may be briefly stated : The assessee in the case is Her Highness Smt. Chand Kanwarji, the Maharani of Alwar, (hereinafter referred to as the assessee ). Her assessment for the year 1960-61 was completed on 26th October, 1962 on a total income of Rs. 48,394. 00 under section 23 (3) of the Income-tax Act, 1922 (hereinafter referred to as the Old Act ). Similarly, the original assessment on the assessec for the assessment year 1961-62 was completed on 3rd January, 1963 on a total income of Rs. 55,930. 00 under Section 143 (3) of the New Act. For these two assessments, the income derived by the assessee by way of interest from bank deposits was treated as earned income and the Income-tax Officer has also accepted the assessee s claim of expenditure on the salary paid to her danghter-in-law. Subseauently. the Revenue Audit staff working under the Comptroller and Auditor General of India, while scrutinising these assessments, brought to the notice of the Department that the Income-tax Officer had wrongly treated the interest income as business income and also that the Income-tax Officer had wrongly allowed the assessee s claim with regard to the salary paid to her da lighter-in-law.

( 3 ) ACTING upon this scrutiny note of the Revenue Audit, the Inspecting Assistant Commissioner wrote to the Income-Tax Officer asking him to rectify these defects by reopening the assessments under section 147 (b) of the New Act. The Income-tax Officer thereupon reopened the original assessments under section 147 (b) of the New Act, and issued notice to the assessee. The assessee objected to the reopening of the original assessments by the Income-tax Officer and contended that all the relevant information was available to the Income-tax Officer at the time of the original assessments and that the Income-tax Officer, after a consideration of the said material, had come to a definite conclusion that the interest income constituted earned income and also that the salary paid by the assessee to her daughter-in-law was an allowable item of expenditure. The Income- tax Officer overruled the assessee s objections on both these points and treated the interest income as unearned income and he also disallowed a major portion of the assessee s claim regarding the salary paid to her daughter-in-law.

( 4 ) THE assessee preferred appeals to the Appellate Assistant Commissioner and again contended before him that the reopening of the original assessments under section 147 (b) of the New Act was illegal, The Appellate Assistant Commissioner accepted this contention and held that inasmuch as all the material facts were before the Income-tax Officer at the time of the original assessments and he had, after a consideration of these facts, arrived at a definite conclusion, he could not by mere change of opinion reopen the original assessments. He, therefore, set aside the re-assessments under setion 147 (b) of the New Act,

( 5 ) AGAINST these orders of the Appellate Assistant Commissioner, the Revenue preferred appeals before the Tribunal. It was pointed out to the Tribunal that the scrutiny note of the Revenue Audit staff and the letter written by the Inspecting Assisant Commissioner to the Income-tax Officer were not brought to the notice of the Appellate Assistant Commissioner and it was contended that these documents co