"We wish to emphasise that the circumstances in which the court will consider exercising its implied "abuse of process" jurisdiction in extradition cases are very limited. It will not do so if, first, other bars to extradition are available, because it is a residual, implied jurisdiction. Secondly, the court will only exercise the jurisdiction if it is satisfied, on cogent evidence, that the Judicial Authority concerned has acted in such a way as to "usurp" the statutory regime of the EA or its integrity has been impugned. We say "cogent evidence" because, in the context of the European Arrest Warrant, the UK courts will start from the premise, as set out in the Framework Decision of 2002, that there must be mutual trust between Judicial Authorities, although we accept that when the emanation of the Judicial Authority concerned is a prosecuting authority, the UK court is entitled to examine its actions with "rigorous scrutiny"
"27. … Extradition involves the issuing of a warrant by a foreign authority which engages the UK's international obligations as well as its domestic legislation. Statutory bars have been enacted which reflect those arrangements, whether Treaty or Framework Decision. There is no scope for more than a residual jurisdiction to preclude the extradition of someone who falls outside the scope of the statutory bars. That is the residual jurisdiction envisaged in the line of cases leading to Belbin, where the contention is that the prosecutor or judicial authority has acted in bad faith, deliberately manipulating proceedings, undermining the statutory regime to the unfair prejudice of the defendant. Such a jurisdiction is consistent with those international obligations only because it is obvious that no prosecutor or issuing authority should behave in the manner described in Belbin as an abuse of the court's process; it is necessarily implicit in the arrangements, and accepted by all participants, that they would not be allowed to do so. 28. Any extension of that jurisdiction however would undermine the statutory process itself and the international arrangements to which they give effect. I do not consider that the residual jurisdiction should be expanded to embrace the Henderson ... principle. If no bar is made out, it is difficult to see why a person who faces no bars to extradition should then not be extradited, other than as a sanction imposed on the requesting authority for not complying with directions or not getting its case in order. Such an approach, which may run contrary to the overall public interest in any given case, and which may be inconsistent with the primary purpose of extradition arrangements, cannot be extracted from the Framework Decision nor the Act."