An appeal lies to the Court of Appeal from a ruling in a preparatory hearing, pursuant to the Criminal Procedure and Investigations Act 1996, on the question of abuse of process. it was important to distinguish two stages of the analysis, both of which might be termed “jurisdictional” but in different senses: the first was the question whether, in principle, an appeal lay under section 35(1) of the 1996 Act from a ruling made in a preparatory hearing on an application to stay proceedings on the ground of abuse of process. That question turned on whether the ruling appealed from was a ruling “on any […] point of law relating to the case” within the meaning of section 31(3) of the 1996 Act. If the answer was “No”, the court should not embark on the task of considering the substance of the appeal. If, however, the answer was “Yes”, a second stage of analysis arose: how should the appellate jurisdiction in section 35(3) be exercised? A conclusion that, in principle, an appeal did lie did not mean that it would be appropriate for the Court of Appeal to exercise its appellate jurisdiction by substituting its judgment for that of the first instance judge. It was not the function of the Court of Appeal, whether on an interlocutory appeal or on an appeal from conviction, to remake the judge’s findings of fact or to perform the balancing exercise afresh, unless the judge had erred in law or approach, taken into account something irrelevant or failed to consider something relevant or reached a decision that no reasonable judge could reach (paras 11, 38, 43).