Tan Cheng Bock v AG [2017] SGCA 50 of a decision, it is useful for demonstrating the soundness – as a matter of policy – of that outcome. This is an important function given that the law is not only meant to be applied but is also, ideally, meant to be understood and appreciated by the people who are governed by it. In that sense, the availability of s 9A(2)(a) advances the rule of law by assuring the governed that the court is applying the law in keeping with the policy imperatives for which it was enacted. There is thus utility in having a provision of the IA which legitimises the outcome of the court’s inquiry in such situations. 50 It also bears mentioning that extraneous material cannot be used “to give the statute a sense which is contrary to its express text” (Seow Wei Sin v Public Prosecutor [2011] 1 SLR 1199 at [21]) save perhaps in the very limited circumstances identified in s 9A(2)(b)(ii) of the IA (see [47(c)] above). This echoes the broader principle that the proper function of the judge when applying s 9A of the IA is to interpret a given statutory provision. Although purposive interpretation is an important and powerful tool, it is not an excuse for rewriting a statute (see [43] above). The authority to alter the text of a statute lies with Parliament, and judicial interpretation is generally confined to giving the text a meaning that its language can bear. Hence, purposive interpretation must be done with a view toward determining a provision’s or statute’s purpose and object “as reflected by and in harmony with the express wording of the legislation”: Public Prosecutor v Low Kok Heng [2007] 4 SLR(R) 183 at [50]. 51 In our judgment, consideration of extraneous material should be tempered by these conditions set out in s 9A of the IA. Further, only material that is capable of assisting in ascertaining the meaning of the provision(s) by shedding light on the purpose of statute as a whole, or where applicable, on the purpose of particular provision(s) in question, should be referred to (Ting Choon Meng at [63]). 25