The Australian Achievement: From Bondage To Freedom by Professor L.J.M. Cooray
18. The Rule Of Law
18.6 Retrospective Legislation
Laws should apply prospectively and not retrospectively A
person should never be made to suffer in law (criminal or
civil) for an act which was not unlawful when he committed
it. Retrospective legislation destroys the certainty of law,
is arbitrary and is vindictive, (being invariably directed
against identifiable persons or groups). Such laws
undermine many characteristics of the rule of law.