P.R. Laws tit. 13, § 890
(a) Whenever in the judgment of the Secretary of the Treasury it is necessary for the proper administration of this tax, he may require any person, by notice for the purpose, to make a return of his assets and liabilities, in such detail and in such form as the Secretary of the Treasury may require, as of such date as the Secretary of the Treasury may specify (but in no case shall such date be more than three (3) years prior to the date of notice).
(b) Whenever it appears that the excess of the assets of a taxpayer over his liabilities exceeds the amount that can be accounted for by adjusting the assets and liabilities declared as of a previous date in accordance with the income reported for income tax purposes, unrealized increases in the value of individual items, and the gifts reported under §§ 881—905 of this title for the intervening period, after making a reasonable allowance for living expenses, such excess may be presumed to arise from an unreported gift, and the Secretary of the Treasury shall proceed to assess and collect a tax thereon, together with such penalties as may be due. For this purpose the Secretary of the Treasury may make such reasonable assumption as he selects regarding the time such gift was made and the age of the person from whom it was received, and such assessment shall not be set aside except upon a clear showing by the taxpayer of a legitimate basis for the discrepancy observed.
History —Apr. 12, 1946, No. 303, p. 782, § 9, retroactive to Mar. 22, 1946.