Whether [CIPAA] applies to construction contracts entered into before the coming into operation of this Act i.e. 15.4.2014. … [25] Thus, in the absence of any such provision, it is apparent that Parliament has not evinced any intention that the CIPAA is to be applied retrospectively. Whilst part of the reason the CIPAA is 6 enacted is to remedy an existing problem, which the law-making body is aware of, Parliament is silent on whether such a remedy was to be applied retrospectively. If Parliament has intended for the CIPAA to be applied retrospectively, given its full awareness of the existing problem, it would have expressly included a provision to that effect. Parliament does not though, and instead in accordance with sub-s. 1(2) of the CIPAA, it came into operation on 15 April 2014 without express provision to the effect that the CIPAA shall come into operation on a date prior to the date on which the instrument of appointment is published which is 15 April 2014 as required under sub-s. 43(a) of Act 388 or shall apply to construction contracts entered into on or before its commencement date. … [45] From the above authorities, it is clear to us that in the absence of express words to such effect, a statute, notwithstanding whether it is procedural or substantive, cannot be applied retrospectively to impair a substantive right. This settled legal position, we would say, accords well with and further amplifies those statutory provisions of the interpretation statute namely Act 388. To reiterate our point, it is important to note that the CIPAA in itself does not contain any provision stating that it has retrospective application. Parliament therefore clearly does not exercise its legislative power pursuant to art. 66 cl. (5) of the Federal Constitution and sub-ss. 2(3), 19(1) and 43(a) of Act 388 to enact the CIPAA with retrospective effect. … [54] In our view, the savings provisions in s. 41 of the CIPAA does not and cannot amount to an express statement by Parliament for the CIPAA to apply retrospectively. ... On a plain reading of s. of the CIPAA, there is no real doubt that all that is provided is that litigation and arbitration proceedings commenced prior to 15 April 2014 are not impacted by the introduction of the CIPAA. The operation of s. 41 is only confined to and restricted by litigation and 7 arbitration proceedings commenced prior to the commencement date of the CIPAA. It cannot be construed to mean, as the learned judge had done in UDA Holdings Bhd, that since construction contracts entered into before the commencement of the CIPAA are not included in ss. 3 and 41 and in view of the generality of s. 2, it follows that the CIPAA applies to them. … [55] We need only say on this aspect that if the legislative intention is for the CIPAA to have a retrospective effect, Parliament would have included express provisions to that effect instead of providing for limiting provisions in ss. 3, 40 and 41 and the general provision of s. 2 and leaving it to the court to imply or infer from these provisions that the CIPAA consequently applies retrospectively to all construction contracts entered into before the CIPAA was enacted. Accordingly, we cannot accept the conclusion reached by the High Court in UDA Holdings Bhd and the submission of learned counsel for the appellant that the CIPAA, in view of ss. 2, 3, 40 and 41, operates retrospectively, as it was posited on the false premise that the generality of s. 2, the exclusion provision of s. 3, the exemption provision of s. 40 and the savings provisions in s. 41 as the only limiting provisions have put to rest the argument that the CIPAA is prospective in its operation. The plain facts is, there are no clear and express words in the CIPAA providing for its retrospective operation. This court must give effect to every word used in a statute and determine the meaning which emanates from it since there is a presumption that Parliament does not legislate and in fact does nothing in vain. As earlier stated, Parliament has fully appraised the existing problems experienced by the construction industry and is fully aware of the mischief the CIPAA seeks to overcome, yet it has elected not to include a clear and express provision that the CIPAA is to be applied retrospectively. … 8 [59] It is apparent from the above passages that where the parties have acted on their contractual rights in respect of a particular clause of a construction contract, such as the pay-when-paid provision in the instant appeals and the cross-contract set-offs clause in Ireka Engineering & Construction Sdn Bhd, ss. 35 and 5 of the CIPAA respectively should not have retrospective effect on the contract between the parties in order to interfere with those contractual rights which have already been vested in and exercised by the respondent. We would go further to say that in such a situation any interpretation that the statute operates retrospectively would prejudicially affect vested rights or the legality of the past transaction which predates the legislation. [60] Accordingly, once a party has acted on its contractual rights at a time when such contractual provisions were permissible, the presumption against retrospection is strong. … [61] It is therefore clear that courts will be slow in concluding that a statute would have retrospective effect if such construction will consequently impact vested rights, contracts, transactions or impose new duties and obligations in relation to past transactions for to do so would be contrary to the presumption that a statute should not be given a construction that would impair existing rights as regards person or property unless the language in which it is couched requires such a construction. The basis of this presumption in this area of the law is no more than simple fairness, and justice which ought to be the basis of every general rule. … [62] In our judgment, the fact that Parliament does not expressly state that legislation will be prospective would be the starting point and thereafter other factors such as fairness and hardship will also be considered. … 9 [70] Given that the CIPAA impacts parties’ substantive rights, a retrospective application of the CIPAA would have the effect of interfering with the basic principle of freedom of contract. … [71] The last remaining point concerns the appellant’s argument that a construction that will promote the purpose underlying the CIPAA shall be preferred to justify the retrospective application of the CIPAA. The principle of purposive interpretation of statute is provided in s. 17A of Act 388. … There is no doubt that the object and purpose of the CIPAA is expressly stated in the long title thereof. However, such purposive approach in our judgment in no way diminishes the trite general presumption of prospectivity of a statute. It ought to be emphasised that the only issue in this case is whether the CIPAA is to have a retrospective application. Therefore, s. 17A of Act 388 must be read subject to the said general presumption and ss. 19(1) and 43 of Act 388 which require clear and express intention to apply the CIPAA retrospectively. … [72] We see no reason, in the lights of our deliberation above, to be persuaded by the appellant’s argument that the CIPAA is a legislation of general application. The provisions of the CIPAA undoubtedly affect the substantive rights of parties and such rights ought not to be violated as it is of fundamental importance to the respondent besides being an essential component of the rule of law. Consequently, the entire Act ought to be applied prospectively. In our judgment, any interpretation that the CIPAA takes effect retrospectively inhibits the exercise of the respondent’s vested right in accordance with the bargain entered into between the parties. The outcome, as earlier indicated, is that both questions of law allowed by this court at the leave stage must be answered in the negative. In the upshot, the entire adjudication proceedings including the adjudication decision are rendered void. The glaring conclusion which emerges is that the appellant is unsuccessful in all of their 10 contentions. Absent any express intention by Parliament that the CIPAA is to be applied retrospectively, the CIPAA can only be applied prospectively. The adjudication decision therefore ought to be set aside. …” (emphasis added).