(2) The Crown Prosecutor was alive to the limited nature of the assistance being offered by YZ. It was, indeed, in contemplation of the Crown Prosecutor's perception of those limitations that it was insisted by the Crown that there be included in the written undertaking the short paragraph marked ….[…*…]…. in the reference made earlier herein to the terms of the undertaking as finally given.
(3) The Crown could have refused to deal with YZ upon the basis of the only undertaking as to future assistance that YZ was prepared to give. The Crown could not, I think, have prevented YZ from informing Blanch J that he was prepared to give assistance in accordance with the undertaking; but I do not see why the Crown could not have told Blanch J that the Crown regarded the proffered assistance as either worthless, (if that were the Crown perception), or of such marginal worth as would not dispose the Crown to call YZ in the trial of Warren, (if that were the Crown perception). It seems to me, however, that the Crown's position was that YZ's evidence was not worthless in connection with the pending trial of Warren; and that, albeit the Crown would have preferred a much greater degree of assistance from YZ, the Crown was prepared, nevertheless, to accept, however grudgingly, what was in fact offered by YZ, and to call him, accordingly, at the Warren trial.
14 For the Crown it was submitted that YZ, at the time he gave the particular undertaking, was in a position to give assistance to the relevant law enforcement agencies as to many more of the alleged co-conspirators than only Warren. It was submitted that YZ was well aware, at the time at which he gave his undertaking, that Warren was in fact senior in years and in ill-health; and that YZ undertook to give evidence against Warren at the latter's trial because, or predominantly because, YZ's true belief at the time was that Warren would never be brought to trial because of his age and ill health, with the result that YZ himself would never be called upon to honour in fact his undertaking to give evidence against Warren.
15 That level of scepticism about YZ is, in my opinion, wholly understandable. I do not think, however, that there is to hand precise and credible evidence which, if accepted, would justify a positive finding that such scepticism has been vindicated. Nor do I think that such scepticism is of itself sufficient to cut down any of the propositions (1)-(3) previously mentioned.
16 It then becomes necessary to consider whether cause has been shown for a finding that YZ, when he resiled from his undertaking, acted "without reasonable excuse".
17 My first impressions, at the hearing of the appeal, were that there was more than a little force in the essential argument put forward by YZ: that is to say, the argument that, by the time he was called to give evidence on 17 April 1997, he had been put in such a position that he faced a stark choice between two evils, of which the lesser was, in his then reasonable perception, to resile from his undertaking.
18 In that connection, it should be acknowledged, in my opinion, that by 17 April 1997 things had happened that might have been thought, very reasonably, by YZ to be threatening as to either his own safety or that of his immediate family. By 17 April 1997 YZ was aware that a copy of his undertaking had come into the possession of Warren, and had been circulated by, or at the instigation of, Warren, widely throughout the criminal milieu to which YZ himself was connected. There had been some very strident media publicity which had conveyed, some of it in the most lurid terms, and to the world at large, that YZ had become a police informer. Some graffiti, having obviously nasty overtones, had been sprayed onto various parts of YZ's then home. YZ himself had been assaulted in prison as a police informer.
19 As I have said, such considerations originally disposed me to think that there might be, indeed, substance in YZ's present contention that his resiling from his undertaking had not been done "without reasonable excuse". Upon further reflection I have come, however, to the conclusion that a positive finding to that effect should not be made. My reasons are, broadly speaking, the following: