The simple ultra vires doctrine was implicitly applied by the High Court of Singapore in Wong Yip Pui v. Housing and Development Board (1984),Wong Yip Pui v. Housing and Development Board [1983–1984] S.L.R.(R.) 739, H.C. (Singapore). The Court did not specifically refer to the ultra vires doctrine in the case, which was not an application for judicial review. See also Estate and Trust Agencies (1927), Ltd. v. Singapore Improvement Trust [1937] UKPC 61, [1937] A.C. 898, P.C. (on appeal from the Straits Settlements (Singapore)) (Singapore Improvement Trust acted beyond its powers by declaring house insanitary as there were insufficient grounds to hold that it was "unfit for human habitation" as required by statute). in which the Court had to determine if the Housing and Development Board (HDB) had the power to compulsorily acquire a flat which had been sold to the plaintiff under the Housing and Development Act.. Section 48A(1)(b) of the Act stated:Wong Yip Pui, p. 742, para. 17.
