Just before midnight on Friday August 1st 1986 Diane Sindall, a 21 year old florist, ran out of petrol on a Birkenhead roundabout. She got out of her car and went to look for a 24 hour petrol station. She was no more than 500 yards from her car when she was struck on the head with a blunt instrument, dragged into an alleyway, stripped half-naked and sexually assaulted.
The following afternoon, Saturday August 2nd 1986, her battered and grossly mutilated body was found. The cause of death was a cerebral haemorrhage following multiple blows to the head. The mutilations included apparent bite marks to her breasts. The crime was obviously sexually motivated, and samples of semen, heavily diluted with rainwater, were taken from the outside of her body.
It was a particularly horrific murder and it caused fear and outrage well beyond Merseyside. Only 5 years earlier Peter Sutcliffe – The Yorkshire Ripper – had been convicted of the serial murders of thirteen women, all of whom had been mutilated after being attacked with blunt instruments.
Now another “Ripper” was at work on Merseyside. It was, said the Liverpool Daily Post, “a ripper-style slaying of a girl with an untarnished reputation.” Elsewhere the unidentified murderer was dubbed the “Beast of Birkenhead.”
A huge police operation began. More than 3,000 statements were obtained. Hundreds of hours were spent on door to door inquiries, The Merseyside Police computer was almost overwhelmed and the force had to beg for extra memory from the Police National Computer.
But all this activity was to little avail. Some witnesses seemed to have seen Diane walking along Borough Road. One saw a young woman – who could well have been her – apparently arguing with a man in a leather jacket.
Hopes of a breakthrough were raised with the finding of the smouldering and largely burnt-out remains of her clothing on Bidstone Hill, some nearby heathland. Police were able to establish that it had been started on Sunday August 3rd, around 24 hours after the discovery of Diane’s body. But the fragments and ashes revealed nothing to identify the murderer.
By the middle of September the hunt appeared to be at a dead end. They turned to the BBC for help. The popular true-crime show Crimewatch featured the case on September 18th. They staged a reconstruction of Diane’s last known movements and of the discovery of her burning clothing. The officer leading the investigation made a direct appeal for witnesses who might have seen someone acting suspiciously on Bidstone Hill at the relevant time. 
This produced a witness, a Mr Griffiths, who said he had seen just such a man, and he provided police with a description, including a “long pointed nose” and a tattoo on his arm. What was more, said Mr Griffiths, although he did not know the man’s name, he recognised him as “Pete” or “Pedro,” and he had played darts with him a few years earlier in a Birkenhead pub.
At once the police started to scour the local pubs for any darts enthusiasts called Pete. On September 23rd they found Peter Sullivan, a local darts enthusiast, who happened to have a fairly large nose and a tattoo on his arm. After weeks without a result here was a plausible suspect.
Mr Sullivan was arrested and placed on an identification parade. Mr Griffiths did not pick him out.
He was then subjected to hours of police interviews. The police decided to refuse him access to a solicitor on the grounds that if a solicitor learnt of facts that were not in the public domain that might hinder their investigations. Under the law as it then was (and remains) that was a decision that they were entitled to make.
Mr Sullivan gave a series of contradictory accounts of his movements on the night of the murder. The Police and Criminal Evidence Act 1984, which contained ground-breaking provisions designed to protect the rights of suspects, had recently come into force but regulations requiring the police to tape record interviews with suspects had not. Despite this, the police possessed the necessary equipment and most of his interviews were tape-recorded. Crucially, however, one was not. In that interview he reportedly broke down in tears and confessed to the murder.
His confession was said to include facts that only the murderer would have known: that a photograph of Diane’s boyfriend and a bank paying-in book was in her handbag. The police also said that he marked on a map the exact spot where her clothes were burned. Unhelpfully he also said that he had killed her with a brick, which did not accord with the pathologist’s evidence. But this mattered little as the police discovered that shortly before the murder he had borrowed a crowbar – which could have caused the injuries – from a neighbour. They were able to recover the crowbar from his house, though a forensic examination found nothing on it which suggested it had anything to do with the murder.
With the confession in their hands, the police finally allowed Mr Sullivan to see a solicitor. He immediately retracted his confession, then repeated it, then re-retracted it. At his trial it was suggested that he had been verbally and physically abused by the police, and then told that if he admitted the murder they would ensure that he got treatment for his mental health instead of being sent to prison. The police denied these suggestions.
By the late 1980s the dangers of false confessions were well-known. It was those very dangers, and the inadequacy of the “Judges’ Rules” that were meant to safeguard the rights of suspects, that had led to the passing of important sections of the Police and Criminal Evidence Act.
The police needed more evidence. The crowbar could not be forensically linked to the murder, and although three brown fibres matching those from Diane’s clothing had been found in his house, they were a common type and were said by the prosecution forensic scientist to be of only “limited value.”
DNA profiling was in its infancy and had yet to be used in a murder trial. In any case, obtaining a DNA profile from the degraded semen samples was considered impossible. Instead, the police concentrated on the injuries to Diane’s breasts. They consulted a local lecturer in dentistry from Liverpool University, Dr John Scott. He told them what they did not want to hear. It was “unlikely” that Mr Sullivan was responsible for the two apparent bite marks. Indeed, he doubted that one of the apparent bite-marks was caused by teeth at all.
Dr Scott’s expertise was limited to “about half a dozen” previous cases, none of which involved what he termed “aggressive” bite marks. He suggested that the police should obtain the services of a someone more experienced and recommended Dr Gordon McDonald of the Glasgow University School of Dentistry, a hugely respected dental pathologist, and a leader in the developing field of forensic odontology. Since 1976 he had held the position of “honorary odontologist” to the Strathclyde Police.
Forensic odontology is of course an important and for the most part an entirely respectable branch of forensic science. It has proved particularly useful in the identification of people killed in fires; when DNA may have been damaged or destroyed teeth often survive intact and can be compared with dental records. McDonald believed that it was possible to do much more. He believed it was possible to identify a particular individual from comparison of his teeth with bite-marks on flesh.
The dangers of bite-mark evidence have since been widely recognised. Numerous studies both from this country and the United States have pointed them out. A 2023 Review by the United States National Institute of Standards and Technology concluded that the three premises on which the “science” was based were flawed. Human dentition is not unique to the individual and any unique characteristics are not necessarily transferred to human skin anyway. Even using the most modern computerised techniques matches are not necessarily reliable, and the techniques available in the 1980s were even more prone to error.
Dr McDonald was untroubled by these doubts. He compared moulds taken from Mr Sullivan’s teeth with the marks on Diane’s breasts. His view was unequivocal: they were a perfect match for Sullivan’s teeth. Dr McDonald discussed his opinion with Dr Scott, who then changed his mind. He now agreed that the marks were caused by Mr Sullivan’s “highly unusual” mouth.
Dr McDonald’s opinion was put to Mr Sullivan in a recorded interview:
“Do you recall that on one day you were here you had teeth impressions taken from you? If you were not on Borough Road and have never met Diane Sindall, how are your teeth marks all over her body? Your teeth marks are particularly distinctive and have gone off to an expert witness with many years of experience. He has examined photographs of bitemarks on Diane’s body and says those tooth marks are yours.”
Mr Sullivan responded:
“No way are my teeth marks on her body. No way. I don’t believe that man at all. I do not go around biting people. My teeth marks are not on her body. My teeth have never been near Diane Sindall. You are talking to Peter here. I do not go around killing people.”
At the trial the “critical importance” of Dr McDonald’s evidence was emphasised in the prosecution opening speech. His tests, said Andrew Rankin QC, left “no doubt” as to Sullivan’s guilt:
“He has absolutely no doubt. The defendant caused those bite marks. He murdered Diane Sindall, beyond argument. That is how important the evidence of bite marks is. This is the critical part of the case, so critical that in my submission you can forget the rest of the case.”
John Kay QC, for the defence – a fine advocate and later a Court of Appeal judge – did his best, suggesting in cross-examination that McDonald had fallen into a trap:
“This is a developing science and you are claiming to have a greater degree of ability to point to particular man than in fact is possible in your field?”
On the contrary, replied McDonald:
“I have presented my conclusions in the most conservative manner I feel I can. I have no doubt in expressing them.”
Quite obviously, if Dr McDonald’s opinion was accepted it could only lead to one conclusion: that Mr Sullivan was the murderer. Dr McDonald’s stellar reputation would have made him an intimidating opponent for any other forensic dentist, and in the event the defence called no-one to contradict him.
Since the rest of the prosecution case rested largely on a confused and retracted confession to the police and an equally dubious “jail-house confession” to a fellow inmate one can see why Mr Rankin felt so relaxed about the jury forgetting it.
Mr Rankin returned to the dental evidence in his closing speech. According to the Liverpool Echo:
“Mr Rankin drew particular attention to the evidence of Scottish forensic odontologist Dr Donald McDonald who had said bite marks found on Diane’s breast could only have come from the mouth of Peter Sullivan.”
[He] said the defence had brought ‘no contrary evidence’ and Dr McDonald’s evidence had been “lucid, coherent, cogent, and compelling.”
Mr Sullivan had given evidence that could hardly be so described. Before going into the witness box his own barrister had presciently warned the jury that Mr Rankin would “make mincemeat of him.”
Mr Rankin put it to him that he was a liar:
“is it not a fact that you are a born and bred liar, a total stranger to the truth and would not know it if it was staring you in the face?”
That probably was a fact, but establishing that Mr Sullivan was an habitual liar was not entirely helpful to the prosecution. It was not just the 14 different accounts that Mr Sullivan gave to the police of his movements on the night of the murder, at least 13 of which must have been lies. One small piece of evidence tellingly demonstrated Mr Sullivan’s tenuous relationship with the truth, and indeed reality. The prosecution had called a witness from the pub where Sullivan had been drinking on the evening before the murder. Amidst laughter from the public gallery he recounted how on the night before the murder Sullivan – a keen but indifferent darts player – had been claiming that he had won £500 playing darts against the then World Darts Champion, Eric Bristow. 
The bite-mark evidence was already central to the prosecution case, and it assumed even greater importance with a surprise development late in the trial. The apparently persuasive point that Mr Sullivan knew facts about the murder that had not been made public was dramatically undermined.
It was revealed that on 28 August 1986 – well before the Crimewatch appeal and several weeks before Mr Sullivan’s arrest – an unnamed “Mr X” had been arrested as a suspect. During his interviews he told the police that he had come across Diane’s body, stolen items from it and then taken and burnt her clothing on Bidstone Hill (as any one of us might do if we came across a half-naked and grossly mutilated corpse lying in an alleyway). Awkwardly for the prosecution, Mr X – just like Sullivan – had told the police various details about the murder that were supposedly known only to the police or the murderer. Prosecution counsel was suddenly put in the awkward position of having to explain to the jury that Mr X had learnt similar details “from Arrowe Park Hospital and also directly through a policeman. He could have learnt about this murder from all sorts of sources.” The defence made the obvious point that if Mr X could have learnt these apparently confidential details from “all sorts of sources” then so too could Mr Sullivan.
(One such source was the BBC, which had told its audience of around 14M Crimewatch viewers that Miss Sindall’s partially burnt Barclays Bank paying in book was found amongst her clothing on Bidstone Hill. They even broadcast a facsimile of the book, complete with burnt edges. It made a nonsense of one of Mr Rankin’s suggestions to Mr Sullivan:
Q: You mentioned to the police about a bank paying in book being at Bidstone Hill. You could only know about that because you handled the contents of Diane’s handbag?)
Mr X was arrested and interviewed several times, but he was excluded from suspicion – the jury were told – because his teeth did not match the injuries on Miss Sindall’s breasts.
But whatever the weaknesses in the confession evidence, and however much the mysterious Mr X’s confession undermined the prosecution case, it did not matter. Given that Dr McDonald’s evidence was confident, uncontradicted and unshaken by cross-examination what else could a rational jury could do but find Sullivan guilty? When the inevitable and unanimous verdict was returned his mother cried out “oh God, no!” from the public gallery. Few others believed in his innocence.
After gaoling him for life, the judge went out of his way to praise the police investigation as “responsible, fair-minded and thorough.” Relatives of Diane expressed relief that her killer had been brought to justice, and some bemoaned the fact that the death penalty was no longer available.
Mr Sullivan was advised by his lawyers that there were no grounds on which he could appeal. He was taken to prison. He had been told that he had to serve a minimum term of 16 years before being eligible for release, if the Parole Board deemed him safe. He continued to deny his guilt and again and again they deemed him unsafe.
In 2007 he tried to persuade the Criminal Cases Review Commission to look at his case. They concluded – and it seems that this was probably correct – that the samples taken from Diane’s body had been so degraded by rainwater that they were unsuitable for DNA analysis. That application went nowhere.
But while he was growing old behind bars, it slowly began to be appreciated that bitemark evidence was not necessarily as objective and reliable as had been so confidently asserted at his trial.
It had been widely used in America. But by 2013, according to the New York based Innocence Project, at least 24 men convicted of murder or rape on the basis of bitemark evidence had had their convictions quashed, generally after DNA evidence proved that the confident assertions of prosecution forensic odontologists were simply wrong.
Amongst those exonerated in America was Ray Krone, who had been twice convicted of the brutal sex murder of a Phoenix woman. (He was granted a retrial after the first conviction – which led to a death sentence – was quashed because of late disclosure of evidence). As in Sullivan’s case the prosecution case against Krone in both trials relied heavily on the evidence of forensic odontologists who claimed that “tooth marks” on the victim’s breasts were a perfect match for his unusual teeth. He spent 10 years on death row but DNA evidence uncovered by the Innocence Project eventually showed that the actual murderer was not Krone but a local man with convictions for various sexual offences. (Since his exoneration in 2002 Krone has been a vocal opponent of capital punishment, and one can see his point).
The successful attacks of bitemark evidence were not at first replicated in Britain. Krone’s case bore some striking similarities to Sullivan’s, but even if he was aware of it Mr Sullivan was a penniless Category A prisoner and had no means of instructing a dental expert, still less of persuading the courts to re-examine his conviction. His application to the CCRC had been rejected.
He was, however, fortunate that two lawyers from the north of England firm Switalskis, solicitor Sarah Myatt and in-house barrister Jim Littlehales, were prepared to work on his case for free.
By the middle of 2019 they had obtained two expert reports which, at last, cast serious doubt on both the bitemark and the confession evidence that had been used to convict him.
First was a report from Iain Pretty, Professor of Public Dentistry at the University of Manchester. Pretty has long argued that whilst bitemark analysis can have a role in forensic dentistry, the identification of particular individuals from bite mark comparison lacks any proper scientific basis. At Sullivan’s trial Dr McDonald had said he had “no doubt at all” that Sullivan’s teeth, and only his teeth, could have made the marks on Miss Sindall’s breasts. Pretty’s view was that such certainty was impossible. Not only was there no basis for concluding that the “bitemarks” must have been made by Mr Sullivan, it was not even clear that they had been made by human teeth at all.
Secondly there was a report from Dr Harry Wood, a consultant psychologist, which highlighted Mr Sullivan’s limited intellectual capacity and suggestibility.
Given that prosecution counsel had told the jury – with impeccable logic – that the evidence was so critical that if they accepted it they could “forget the rest of the evidence,” one might have thought that a credible report doubting it could trouble the Court of Appeal.
A little knowledge of criminal procedure is needed to understand what happened next.
Normally anyone wishing to appeal must do so within 28 days of the conviction. In Mr Sullivan’s case over 32 years had elapsed. However, the Court of Appeal may, and quite often does, extend the time limit. In fact, where it judges the grounds of appeal are strong the passage of time alone hardly ever constitutes a significant hurdle. Conversely, where it considers the grounds are weak it will enforce the 28 day time limit rigorously.
Anyone wishing to appeal a conviction must first obtain permission to do so. This is initially a paper – or these days an electronic – exercise. Proposed grounds of appeal are placed before a single High Court judge. If he or she considers that they are “arguable” leave to appeal is given, and the case is then listed in front of three judges in the Court of Appeal.
If leave is refused by the single judge it is not necessarily the end of the road. The request for permission can be renewed to the Full Court, consisting of 3 senior judges. As with the single judge, if the Full Court judges the grounds to be arguable it will grant leave to appeal. The actual appeal is then heard by a separate court at a later date.
At both the application for leave and the final hearing an appellant can submit fresh evidence. Persuading the court to consider it, though, can be an uphill struggle.
In deciding whether to take the fresh evidence into account the Court applies S.23 of the Criminal Appeal Act 1968 which sets out “particular” matters to which the Court should having regard:
“(a) whether the evidence appears to the Court to be capable of belief;
(b) whether it appears to the Court that the evidence may afford any ground for allowing the appeal;
(c) whether the evidence would have been admissible in the proceedings from which the appeal lies on an issue which is the subject of the appeal; and
(d) whether there is a reasonable explanation for the failure to adduce the evidence in those proceedings.”
These are considerations for the court to “have regard,” they are not absolute requirements. The approach the Court says it takes to fresh evidence is set out in a case called Lundy [2013] PC 28:
“If the evidence is not credible, it should not be admitted. If it is credible, the question then arises whether it is fresh in the sense that it is evidence which could not have been obtained for the trial with reasonable diligence. If the evidence is both credible and fresh, it should generally be admitted unless the court is satisfied at that stage that, if admitted, it would have no effect on the safety of the conviction. If the evidence is credible but not fresh, the court should assess its strength and its potential impact on the safety of the conviction. If it considers that there is a risk of a miscarriage of justice if the evidence is excluded, it should be admitted, notwithstanding that the evidence is not fresh.”
In practice the Court is notoriously reluctant to admit fresh evidence. “The trial,” the judges will say, “is not a dress rehearsal.” Quite often the Court will declare that the fresh evidence is “incredible” or “unworthy of belief.” In one notorious case even an admission on oath by the main witness in a serious sex case that her evidence at the trial had been a pack of lies was not enough to persuade the Court of Appeal. Her retraction, though not her original evidence, was was deemed by the Court to be “demonstrably unreliable.”
If the fresh evidence can’t reasonably be described as incredible, the Court may still decide that it is irrelevant, or that it would have had no effect on the verdict.
Back to Mr Sullivan’s attempt to appeal. Armed with a report casting doubt on the “critically important” bitemark evidence and a report casting further doubt on the reliability of his confession you might have thought, if you were not familiar with the way these things tend to work, that the Court would have considered his appeal was at least arguable. After all, apart from the bitemark and his retracted confession the other evidence connecting him to the murder was a “jail-house confession”, a weak posssible link based on two commonly found fibres and evidence from a neighbour that he had borrowed a crowbar the day before the murder. No trace of blood had been found on the crowbar recovered when Sullivan’s house was searched.
In December 2019 the reports were placed in front of the single judge, together with a request for leave to appeal and an extension of time in which to do so.
The single judge’s response was to refuse both applications. Whilst his statement of reasons is not a public document, Mr Sullivan renewed his applications to the Full Court, and its judgment ([2021] EWCA Crim 1332) is publicly available although only behind a pay-wall with a stern warning against republication without permission.
The single judge dealt first with the application for an extension of time. He was critical of the delay between Mr Sullivan obtaining the reports of Professor Pretty and Dr Wood and the lodging of the application for leave to appeal on December 3rd 2019 (Prof Pretty’s report was dated January 28th 2019 and Dr Wood’s 23 June 2019):
“… in the circumstances of this case the court expects detailed reasons for the delay, including a detailed history of the efforts made to appeal against the conviction between the date of conviction and the date upon which the application for leave was lodged. No such chronology has been submitted in this case. In particular there is an absence of detail relating to efforts made to obtain odontology evidence identifying when and from whom the reports were bespoken. Furthermore, no explanation has been given for the delay between the obtaining of the reports from Professor Pretty and Dr Wood and the lodging of the application for leave to appeal.”
The reasons given for the delay were, he said “wholly inadequate” and he refused to grant the extension of time for the appeal to proceed.
It is unlikely that Mr Sullivan was twiddling his thumbs in his prison cell because he couldn’t be bothered to get on with his appeal or prepare his chronologies. Perhaps the application did not contain all the details they should have done about the “bespeaking” of the reports, and no doubt a chronology would have helped. Possibly there are even cases where such criticisms could be decisive. Here they reek of procedural pettifogging. Mr Sullivan had no money, no training in legal procedure, no scientific expertise, was serving a life sentence in a top security prison, and had been described, unkindly but not altogether inaccurately as “retarded” and “a simpleton.” He was entirely reliant on such help as his lawyers were able to provide. For their part, his lawyers – and one presumes the new experts too – were working without payment.
In fairness, the single judge did not reject the application only for these reasons. He went on to consider the substance of the appeal: the two expert reports each casting serious doubt on the strength of the prosecution evidence at trial. The new reports came from wholly reputable experts. They could hardly be rejected as “not credible.” So the judge gave the next most popular reason that the Court likes to give for rejecting fresh evidence: that it would have made no difference to the safety of the conviction.
“He pointed out that the prosecution case didn’t depend upon the evidence relating to bite marks; that that evidence was but one element of a multi-faceted circumstantial case. In addition to the various admissions of guilt that had been made by the applicant, both to police officers and to a fellow prisoner, the other evidence included his presence near the scene of the murder at the relevant time, some forensic evidence relating to fibres from his clothing, the fact that the fatal injuries were consistent with them having been caused by a tool known to have been in the applicant’s possession, and his knowledge of details and facts that were not in the public domain which were consistent with guilt.”
We don’t know exactly what material the judge was supplied with in Mr Sullivan’s application. Moreover, the judges who consider these applications are extremely busy, and the amount of time they can devote to written applications for permission to appeal is obviously limited. But giving all due allowance for those facts, that reason for refusing even permisssion to appeal, was even more absurd than grumbling about the absence of a chronology. The most cursory reading of the case would have revealed that the bite-mark evidence was critical to the prosecution case. As Prosecution counsel had told the jury:
“The defendant caused those bite marks. He murdered Diane Sindall, beyond argument. This is the critical part of the case, so critical that in my submission you can forget the rest of the case.”
Mr Sullivan was not satisfied with the single judge’s refusal of leave to appeal and took his application for permission to appeal 
to the Full Court.
There is now something of a mystery. The judgment identifies the case as a “non-counsel application,” although the case was in fact listed “for hearing” in Court 8 of the Royal Courts of Justice on 16 March 2021. It is very unusual for prisoners renewing applications for leave to appeal to be given permission to appear in person, even by video link (in fact I have never heard of it happening). Nor (as one would expect if it had happened) does the judgment say that he did so. Mr Sullivan had presumably had legal assistance from the lawyers at Switalskis to instruct the experts and draft the necessary grounds of appeal. Having done so much work without payment I can’t understand why they – or counsel – would not have been able to represent him in court.
Whether or not there was any oral argument (and it looks as though there was not) the 3 judges hearing the renewed application for leave needed just 10 somewhat petulant paragraphs to dismiss them. The gist of their judgment was “why are you wasting our time with this hopeless application?”
“At trial the evidence of the dentist was capable of being challenged by the defence, and the evidence relied on by the prosecution disclosed the change of mind of one of the experts. The single judge concluded that even if Professor Pretty’s evidence qualified as fresh evidence for the purposes of the Criminal Appeal Act, it would not be evidence that would be capable of rendering his conviction unsafe.”
The suggestion that “the evidence of the dentist was ‘capable of being challenged’ by the defence” glides over the significant point that “the dentist” was Dr McDonald, at the time of the trial the High Priest of Forensic Odontology. No other dental expert was available to challenge him on Mr Sullivan’s behalf. Now there was credible evidence that the “critical” bitemark evidence was wrong but in the eyes of the Court of Appeal whether McDonald’s evidence was right or wrong was a mere detail. What really mattered was that the defence had been “capable” of challenging his evidence.
“We agree” said the Court, “with the analysis and conclusions of the single judge.” They refused to extend the time limit for applying for leave to appeal, the effect of which was to bring Mr Sullivan’s attempt to appeal to an end.
Although the full text of Prof Pretty’s report has not been made public, it is obvious from the judgment that it undermined the “certainty” expressed by Dr McDonald. Prof Pretty’s view was that there is no scientific basis for the identification and analysis of human bite marks on skin; and in Prof Pretty’s view the injuries to Ms Sindall could not be identified as human bite marks anyway.1 The judges’ “analysis” (if it deserves such a grand word) was that even if Dr McDonald’s evidence had been discredited by Prof Pretty the conviction remained safe; indeed that it was not even arguably unsafe.
This was – bluntly – nonsense. Even if it had been true that the other evidence was strong, it would still have been nonsense. The significance of the bite-mark evidence was now reduced to to literal irrelevance.
What was left of the prosecution case without Dr McDonald’s “lucid, coherent, cogent, and compelling” evidence?
Was it the disputed confession of a simpleton, made in the absence of a solicitor, that wrongly described carrying out the murder with a brick? The confession that was just part of a whole series of demonstrably false statements made by a man known for telling ridiculous lies? The confession, the doubtful reliability of which was further undermined by fresh evidence from a forensic psychologist, who described Mr Sullivan as of “low intelligence, highly suggestible and highly compliant.”
Was it the risibly dubious alleged – and of course unrecorded – jail-house confession to a fellow prisoner with an obvious motive to lie?
Or perhaps what swung it for the judges was the presence of a few commonly found fibres, admitted by the prosecution at the trial to be of “limited value.”
There was not the slightest “analysis” of why, after a hideously bloody murder, no traces of blood from the victim were found on or around Sullivan, even though on the prosecution case throughout his meticulous disposal of all forensic traces he had inexplicably kept what the prosecution claimed was the murder weapon in his house, instead of at the bottom of the Mersey.s
Nor was any consideration given to the mysterious “Mr X,” cleared as a suspect only because his teeth were said not to match the injuries on Diane’s breasts.
Instead of conceding that the apparent demolition of the main prosecution evidence might, at least, raise an argument about the safety of the conviction, the judges decided that it did not even deserve to be heard.
There the matter might have ended, with Sullivan remaining behind bars while the legal establishment, if it considered the matter at all, remaining smugly satisfied with the less than rigorous analysis of four senior judges.
Fortunately it did not end there. Events over the next three years demonstrated that the Court of Appeal – not for the first time in a murder case – had got it hopelessly and catastrophically wrong. Having been denied the opportunity even to argue his appeal in 2021, Mr Sullivan applied again to the Criminal Cases Review Commission.
The CCRC decided to look again at the semen swabs taken from Miss Sindall’s body. This time a newer technique was used: Y-STR profiling. This obtained a profile which could not have come from Mr Sullivan, (or her fiancé). It had obviously come from her murderer.
The Prosecution instructed their own DNA experts. They reached the same conclusion.
The matter was sent back to the Court of Appeal which heard the case in May of this year. The Crown did not dispute that the DNA evidence meant that Mr Sullivan’s conviction was “unsafe.”
At the appeal the CCRC also relied upon an updated report from Prof Pretty, which was in much the same terms as that regarded as inconsequential by Court in 2021, save that he drew attention to the fact that neither the British Association of Forensic Odontology nor the equivalent body in the United States any longer endorses the positive identification of suspects by reference to bite marks. There were also further reports confirming Mr Sullivan’s mental vulnerability, with a Professor Shepherd pointing out that he was:
“extremely vulnerable in an interrogative situation” [because of] “limited intellectual functioning, problems with self-expression and disposition to acquiese, yield and … be controlled and internal pressure to speak without reflection and to … fabulise.”
Faced with overwhelming evidence that the killer was not Mr Sullivan the Court could no longer pretend that the conviction was safe. The absence of a chronology in 2021 was now immaterial.
This time there was a proper hearing with both sides represented by leading counsel. Whilst accepting that the conviction was obviously unsafe because of the new DNA evidence, the CPS argued that the 2021 Court had nevertheless been absolutely right to reject his application for permission to appeal. It was an odd and unnecessary argument, given that all parties accepted by then that Mr Sullivan was an innocent man who had been the victim of an atrocious miscarriage of justice.
Nevertheless, Duncan Atkinson KC submitted that the Court of Appeal had been quite right to reject Mr Sullivan’s attempt to appeal in 2021. The bite-mark evidence, he said, was regarded by the Court of Appeal as “part of the case but not the significant part, we submit that is a proper analysis. … It was not the central evidence in the case against the appellant.”
With all due respect to Mr Atkinson that was an extraordinary submission. If Dr McDonald’s “cogent, coherent, compelling and lucid” evidence which left absolutely no doubt that Sullivan was the murderer was not the central evidence in the prosecution case, what else could be? It was a particularly odd submission because Mr Atkinson’s predecessor at the trial had repeatedly emphasised the “critical” importance of Dr McDonald’s evidence. Still more remarkably the Court of Appeal swallowed it in full, with Holroyde LJ saying in his judgment “we … agree with the reasons then given [by the Court in 2021] for concluding that, in isolation, it did not cast doubt on the safety of the conviction.”
There are many depressing conclusions to be drawn from Mr Sullivan’s ordeal, none of which are new, but all of which tend to get forgotten until the next exposure of some terrible miscarriage of justice.
Experts can and do get it spectacularly wrong. Renowned and uncontradicted experts are no exception.
Juries are far from infallible, and can all too easily arrive at the wrong verdict, but it is not always their fault. Given Dr McDonald’s confident and unchallenged testimony it would have taken an irrational jury to have come to any other conclusion but that Sullivan was guilty. But given that juries do regularly make mistakes, it makes it all the more important that the Court of Appeal is prepared to correct them.
Sometimes judges give the impression – no doubt quite unintentionally – of looking for any remotely plausible argument to uphold a conviction rather than genuinely asking whether the conviction is in fact safe.
The view of the 2021 Court of Appeal that the bite-mark evidence could be effectively discounted in assessing the safety of the conviction might, if one was being extremely generous, be explained by the Court not having been given full information about the case. But that does not excuse a refusal even to give leave to appeal when the true importance of the bitemark evidence could have been explored in the context of the case as a whole.
Perhaps the outcome in 2021 would have been different if Mr Sullivan had been represented by counsel at his renewed application for leave to appeal. At the very least, had he been represented I doubt if the Court could have dismissed the significance of the bitemark evidence so peremptorily. Why he was not represented we do not know.
The 2025 court of course did quash the conviction. But in doing so it too accepted the demonstrably preposterous submission by Counsel for the Crown that Dr McDonald’s evidence had not been “central” to the case against Mr Sullivan, thereby absolving the 2021 Court of any blame for rejecting his attempt to appeal. It is almost as if there was an institutional inability to contemplate an appalling vista: that the Court had made an atrocious decision in 2021 that delayed the exoneration of an innocent man by 5 years, and – but for the fortuitious fact that the semen samples yielded DNA – would have prevented his conviction ever being overturned.
The Criminal Cases Review Commission has largely escaped blame, but it may have been lucky to do so. It was, of course, the CCRC that eventually referred the case back to the Court of Appeal, leading to the 2025 hearing which quashed the conviction. But should the Commission have acted earlier? When it was first approached by Mr Sullivan in 2007 there was no technique which could have been relied upon to produce a DNA profile from the swabs. But it was well-known that forensic science was constantly developing. Had the CCRC kept the case under proper review then as soon as Y-STR profiling became widely available – which it did in 2015 – it could have reopened the case. And why did the CCRC not examine the bitemark evidence more carefully? By 2013 there had been numerous well-publicised exonerations in America after similar evidence had been discredited. It should at least by then have been obvious that a re-examination of Dr McDonald’s evidence was needed. Had the CCRC investigated the case proactively after 2008 it does seem likely that both DNA and bitemark evidence pointing to his innocence might have been available long before 2025.
Perhaps the worst part of it is that Mr Sullivan may receive no compensation at all . Even if he is lucky enough to receive something, his compensation is capped at £1.3M. Most people would feel that £1.3M hardly compensates for even one year year in prison as a wrongly convicted sex murderer, let alone 38.
(In 2023 Merseyside Police reopened their investigation into Diane Sindall’s murder. It remains a live investigation and they are actively seeking information from members of the public.)
1See also Sullivan [2025] EWCA Crim 772 at para 29.
