This article examines Art 12 equality jurisprudence with specific reference to the case law and legal discourse over the constitutionality of s 377A of the Penal Code (Cap 224, 2008 Rev Ed), which is paradigmatic, in terms of attracting legal and political controversy. How the multi- vocal concept of equality is interpreted, implicates interpretive method, rights adjudication and the appropriateness of a “moral questions” doctrine in advocating modest, calibrated judicial review in addressing morally controversial questions. In Singapore, the prevailing “reasonable classification” test and the accompanying presumption of constitutionality of legislation has attracted two primary criticisms. First, that it has been misapplied; second, that the test itself is too deferential in according primary weight to the “reasonableness” of Parliament and should be replaced by a more robust test of judicial scrutiny. The article contests the argument that s 377A fails to satisfy the reasonable classification test, particularly because it serves no purpose or an inadequate purpose given its original rationale. It argues that calls to revise the reasonable classification test in favour of a preferred vision of substantive equality constitute an unwelcome invitation to “rightism” and an outcome-oriented “living tree” approach to judicial review, which trades in value arguments based on an egalitarian liberal theory of the good. The extensive coverage of the above discussion necessitates publication of the content over two discrete yet connected articles. The first of which is this article which unpacks the orientation and method of “rightism” in relation to general approaches towards construing Pt IV liberties and sets forth the extant reasonable classification test, which disfavours a rights-driven path of judicial activism, in distinguishing between arguments for constitutional interpretation and for constitutional change.