I congratulate the hon. Member for Wolverhampton, South-East (Mr. Turner) on his choice of topic. I am here not, as has just been suggested, merely to hold the line, but to set out the background to the case and explain the way in which it has been dealt with up to this point.

It is right that miscarriages of justice, and the possibility of miscarriages of justice, should be a matter of the highest public concern. Such concern for justice is one of the hallmarks of a civilised democracy. Our criminal justice system, at all its stages, must work so as to protect the innocent while properly punishing the guilty.

The Government have been responsible for a series of major reforms to the criminal justice process, up to and including the Criminal Procedure and Investigations Bill now before Parliament. In the Criminal Appeal Act 1995 we introduced the most important and far-reaching change of recent times to the procedures for reviewing criminal cases in the last resort. Work is well under way to establish the new Criminal Cases Review Commission, which several right hon. and hon. Members have mentioned. We intend the commission to start its work later this year.

Until then, the responsibility for considering cases of last resort rests with my right hon. and learned Friend the Secretary of State for the Home Department, as it has done with Secretaries of State since the turn of the century. It is a responsibility which all Secretaries of State, and their officials, have taken most seriously. The liberty of the citizen is at stake. So is justice, and the security of the public.

Cases such as the one highlighted by the hon. Member for Wolverhampton, South-East can sometimes become the subject of intense and impassioned lobbying and campaigning by people who no doubt sincerely believe in the innocence of those convicted. The task of Secretaries of State, however, is not about deciding or believing in guilt or innocence. Their task is to reach a judgment on all the available evidence, and to decide whether the case should go back to the Court of Appeal.

Certainly, Secretaries of State must listen and pay attention to those who campaign and argue with such feeling. But at the end of the day the decision in each case must be taken calmly, objectively, in the light of all the evidence. The same principles and the same careful judgment must be applied to each and every case, whether or not it is one known to the wider public, and regardless of the degree of clamour or otherwise that may surround it.

The criteria that successive Secretaries of State have applied in considering cases are well known. There must normally be some new evidence, or other consideration of substance, touching the safety of the conviction. New, in this case, means not previously put before the courts or available to be put before the courts. Those criteria do not fetter the overall discretion, and exceptional cases have been referred outside the criteria.

The general thrust found expression in a slightly different way, by Lord Justice Simon-Brown in the divisional court judgment in Hickey and others. He said that the question to be asked was: could the new material reasonably cause the Court of Appeal to regard the verdict as unsafe? In applying those criteria to the case before him, the Secretary of State is bound to look at the evidence in the case as a whole, and to consider the weight and cogency of any new matters in relation to the overall picture. I have heard it argued, in relation to this case and perhaps to others, that the Secretary of State should immediately send any case in which there is credible new evidence straight to the Court of Appeal.

That is quite mistaken. It is also plainly absurd, because if that happened there would be no purpose in having a role for the Secretary of State, or for the new commission. Every convicted person could simply take his or her evidence straight back to the Court of Appeal, which would become clogged with hopeless cases.

Of course the threshold applied by the Secretary of State in deciding whether to refer a case to the Court of Appeal is lower than that which would be applied by the court itself when deciding whether to allow an appeal. But the Secretary of State is entitled to take a view of the weight and cogency of matters placed before him, in the light of the overall picture. Indeed, it is his duty to do so.

In relation to the particular case on which this debate has focused, there is a long and involved history of reviews and investigations spanning the 17 years since the convictions of the four defendants. It has sometimes been suggested—indeed, the hon. Member for Sunderland, South (Mr. Mullin) and others suggested so again today—that simply because there have been so many investigations, the case should be referred again to the courts. That is false logic.

Successive Secretaries of State have been determined in the interests of fairness to have all the new matters put before them fully and properly investigated, however slight or implausible some of these matters may have appeared at first sight. If we investigated only matters bound to lead to a reference to the Court of Appeal, we should quite rightly be criticised for dealing with cases superficially, and for seeking justice on the cheap.

At this point I would like to pay tribute, as I have done before, to the quality of the investigation work carried out in the case, especially by the Merseyside police in the two most recent inquiries. Those inquiries have been exceptionally rigorous and exhaustive. Every lead has been followed. Witnesses have been interviewed and re-interviewed. The most painstaking research has been carried out. Considering the time that has elapsed since the events of the case, that is a formidable achievement.

We are fortunate that such expertise and energies have been applied to the illumination of this case—work that is by no means untypical of the quality of police work in other miscarriage investigations. Parliament was wise to ensure that such skills and expertise will also be available in future to the Criminal Cases Review Commission.

The comprehensive and meticulous nature of these inquiries can be judged from the substantial volume of statements and other material that has been disclosed to the solicitors for the four men, in accordance with the divisional court judgment in ex parte Hickey and others. That was an important judgment. It acknowledged that there had to be a balance in matters of disclosure, and that in some circumstances it would be right for material to be kept confidential. I assure hon. Members that we have gone out of our way in the present case to see that the interests of fairness are met, by providing all the material that is, in our judgment, relevant to the provisional conclusions that we have reached.

As we announced on 7 December, our provisional conclusion, having given the most careful consideration to all the material in the case, and having applied the criteria that I explained earlier, is that the case should not be referred back to the Court of Appeal. We have set out our reasoning in detail and provided the supporting material. On Monday afternoon this week we received a 34-page submission from the solicitors acting for those who were convicted. I understand that that is only a partial response and that the solicitors intend to make further submissions at an unspecified later date. We shall of course consider most carefully the points that have been put to us.

On our provisional conclusions and the response from the solicitors, I do not want to anticipate or prejudge our final consideration, but I propose to set out the evidence on which our provisional conclusions are based and, where possible, to respond to some of the points that hon. Members have made. If there are points that I cannot immediately answer or if we run out of time, I will ensure that those points are taken into account before a final decision is taken.

As I explained earlier, the Secretary of State's task is to consider any new matters in the context of the evidence, old or new, as a whole. That includes of course evidence that formed the prosecution case at trial and that has not been set aside by the Court of Appeal. In the present case, much of the evidence was examined by the Court of Appeal in 1989, following a reference of the case by my right hon. Friend the Member for Witney (Mr. Hurd). The appeal hearing was, at the time, unprecedented in its length—hon. Members have referred to it—and the court's judgment ran to 216 pages. Clearly, any fresh consideration of the case must have regard to the existing evidence and to any view that the Court of Appeal may have taken about that evidence on a previous occasion.

Recent representations in the case have focused largely on the case against Patrick Molloy, but there is separate evidence against each of the four convicted men. Against James Robinson there is the evidence of Mervyn Ritter, Helen Johnston, James Dundas-Ure, Patricia Copus and Peter Bryant. There was also direct evidence identifying Mr. Robinson at the crime scene and evidence of association between Mr. Robinson and the others, evidence of his possession of a gun, and evidence of his reaction when police officers asked him about the gun.

In 1989, the Court of Appeal found Mr. Ritter's evidence in the case to be worthy of belief, despite its acceptance of his reputation as a confidence trickster and a liar. The court found nothing inherently unreliable in Helen Johnston's evidence and nothing in what it had heard to cast doubt on the verdict in so far as it depended on Mr. Dundas-Ure's evidence. It found nothing to justify rejection of Peter Bryant's evidence or to cast doubt on the reliance that the jury may have placed on the evidence of Miss Stagg, a schoolteacher who identified Mr. Robinson as having been at the crime scene at the material time. The court concluded that the case against James Robinson was and remained strong and convincing.