"The general rule of the common law is that a statute changing the law ought not, unless the intention appears with reasonable certainty, to be understood as applying to facts or events that have already occurred in such a way as to confer or impose or otherwise affect rights or liabilities which the law had defined by reference to the past events. But, given rights and liabilities fixed by reference to past facts, matters or events, the law appointing or regulating the manner in which they are to be enforced or their enjoyment is to be secured by judicial remedy is not within the application of such a presumption. Changes made in practice and procedure are applied to proceedings to enforce rights and liabilities, or for that matter to vindicate an immunity or privilege, notwithstanding that before the change in the law was made the accrual or establishment of the rights, liabilities, immunity or privilege was complete and rested on events or transactions that were otherwise past and closed. The basis of the distinction was stated by Mellish LJ in Republic of Costa Rica v Erlanger (1876) 3 Ch D 62. 'No suitor has any vested interest in the course of procedure, nor any right to complain, if during the litigation the procedure is changed, provided, of course, that no injustice is done' (1876) 3 Ch D, at p 69."