Lacey was not interested in the chaotic debris in the hallway, or the swarm of bluebottle flies on the stairs, as she made her way through the house at No 9 Downshire Hill in Hampstead on a warm June afternoon in 2006. But as she approached a room to her right, which was piled high with an assortment of papers, she let out a bark and started digging at the mess in front of her with her paws. What had caught the interest of Lacey, a black-and-tan German shepherd attached to the Metropolitan police’s dog unit, was a decomposing body.

The body turned out to be that of the householder: a wealthy and reclusive author and photographer called Allan Chappelow, aged 86. His skull had been crushed and many of his ribs broken. There were extensive fractures to his neck, which suggested that he had been strangled, and the top half of his body was covered with congealed wax and burn marks. And so began a murder investigation that remains, in many aspects, unresolved to this day.

The police had been dispatched to the dilapidated house in one of north London’s most desirable streets, a short stroll from Hampstead Heath, after Chappelow’s HSBC bank branch became concerned about suspicious transactions carried out with his card. Within weeks of finding the body, detectives had traced the person who had been using the stolen bank details: a 45-year-old Chinese exile called Wang Yam, who was now in Switzerland. They believed he had stolen Chappelow’s bank details from the letterbox at the front of his house and, perhaps when confronted, killed him. In September 2006, Wang was detained by the Swiss police, brought back to England and charged with fraud, theft and murder.



Between his arrest and the start of the trial, it emerged that Wang had acted as an informant for MI6 in London for a number of years. Wang was well placed to be an informant for Britain’s foreign intelligence agency. He had family links with China’s first communist leaders, he was opposed to repressive measures taken by Beijing, and he was something of a computer expert. When he finally stood trial at the Old Bailey in 2008, journalists were ordered to leave the court on the grounds of national security. It was the first murder case in modern times to have been held in such secrecy. Wang claimed that, at the time of his arrest, he had infiltrated a group of gangsters and fed information to what was described in open court as the “appropriate authorities”.

While he admitted he had fraudulently used Chappelow’s bank details, Wang has always denied involvement in the murder. After two trials – the jury could not agree on the murder charge in his first trial – he was convicted of murder, theft and fraud, and jailed for life with a recommendation that he should serve at least 20 years. But there is new evidence that casts doubt over Wang’s conviction.

Before, during and after the trial, the government went to extraordinary lengths to ensure that details of Wang’s links with MI6 would remain secret. Two cabinet ministers told the trial judge that Wang’s entire defence must be heard behind closed doors. A contempt order issued by the judge prevents the media from speculating about the reasons for the secrecy.

In 2013, Wang contacted the Guardian from prison, protesting his innocence of the murder. In January 2014, we wrote about the inconsistencies in the case against him. Following our publication of the story, a fresh witness, who lived only a few doors from Chappelow, got in touch. This new witness told us that, after Wang was already in custody awaiting trial, he too had encountered someone interfering with his letterbox. When he confronted the intruder, he was threatened with a knife. This evidence was given to local police, who did not make the connection with Chappelow’s murder and so did not pass it on to the murder inquiry or the defence team.

Now in the 11th year of his sentence, Wang, who is being held at Lowdham Grange prison in Nottingham, still protests his innocence. Since the trial, another witness has come forward with accounts of Chappelow’s private life that suggest other factors may have been involved. Neighbours have offered more information; one, Thomas Harding, has even written a book on the case, Blood on the Page, which throws new doubts on the safety of Wang’s conviction. Investigators found signs that someone else had recently been in the house: cigarette butts, footprints, a recently used sleeping bag, and condoms. No DNA, fingerprint or footprint evidence linked Wang to the murder scene, and it remains a mystery as to who had been in the house.

But if Wang was not responsible for the murder, who was? Very little was known about the dead man, Allan Chappelow. What reasons might someone have had for killing him?

Allan Chappelow inherited the Hampstead house after his father died in 1976, and, for most of the rest of his life, he lived there alone. He seems to have shown as little interest in its upkeep as he did in his own appearance, which neighbours described as unkempt. Harding, who investigated Chappelow’s background for his book, remembers him as “the peculiar old man” who lived down the street. The house, which stood out like a rotten tooth among its gleaming neighbours, gradually deteriorated into a chaotic shambles, and by the time of Chappelow’s death, it looked more like an abandoned squat than the home of a literary author: the kitchen was an unhygienic jumble of tins and utensils, the wallpaper peeling, the roof leaking, piles of manuscripts and book proofs littered the rooms, and his bedroom was like a dosser’s. The garden was overgrown and untended.

Chappelow was the product of an educated, socialist family, whose liberal-leaning father, a successful decorator and upholsterer, had moved to Denmark rather than be conscripted into military service during the first world war. At the end of hostilities, the family returned to London and bought 9 Downshire Hill. Allan grew up in a politically progressive home; his parents were active members of the Fabian Society. At the onset of the second world war, the bookish Chappelow was faced with the same dilemma as his father, as well as his schoolboy hero, George Bernard Shaw, who had refused to fight in the first world war and was strongly opposed to the second. He applied for conscientious-objector status and was sent to work as a farm labourer in Hampshire.

Facebook Twitter Pinterest Allan Chappelow. Photograph: Metropolitan Police/PA

After the war, he took a degree in moral philosophy at Cambridge; after graduating in 1949, he took photos of people in the public eye whom he admired. Through family connections, he met and photographed the writer HG Wells and the economists and reformers Sidney and Beatrice Webb. In 1950, he set off on his motorbike – an enduring passion – to Shaw’s home in Hertfordshire to ask if he could interview and photograph him. Shaw rebuffed him, saying “an old skeleton at 93 and a half is all that is left of me. Better leave well alone.” Undeterred, Chappelow wrote back to him: “Shame on you! Pshaw! Why you’re SUPERMAN!” He returned, and was eventually granted an audience. Chappelow’s interview with and photograph of Shaw were published in the Daily Mail.

A trip to Russia in 1952 to satisfy his own curiosity led to a well-received book, Russian Holiday, published in 1955 at the height of the cold war. It concluded with a plea for tolerance: “the average Russian … is an amiable, good-natured human being with much the same basic needs as the man in the street of any other nation …Ignorance breeds fear. Fear breeds hate. Hate breeds hysteria. And hysteria can lead to war.” But Shaw remained his chief interest. Two volumes, Shaw the Villager and Human Being (1961) and The Chucker-Out (1969), with an introduction by Vera Brittain, followed. His income from his writing was small, but he led an ascetic life and had few expenses.

There were few visitors to 9 Downshire Hill, and no evidence of any long-term relationship. Most relatives assumed he was gay; a video of a gay pride march found among his belongings might seem to support this. But he was not a complete recluse. He travelled abroad on package holidays and, shortly before his death, went to Texas to carry out more Shaw research at the university. The last family member to see Chappelow was his cousin, Patty Ainsworth. They met in Austin, Texas, where Chappelow devoured the Shaw papers in the university archives. Chappelow told Patty and her husband that he had lived in the same house for six decades and was “proud of it”.

Even in its sorry condition, the house and his estate was valued at £4m. Chappelow died intestate, and the police had a job on their hands to contact any relatives. The first suspicion, given his address and his apparent isolation, was that someone killed him because they wanted his money.

Wang Yam certainly needed money. A Chinese dissident and graduate in computer technology, he had moved to London and applied for asylum in 1991. But in spite of his education and experience, once settled in the UK, he turned out to be a terrible businessman, and went bankrupt twice, owing vast sums.

Wang was proud to tell people that he was the grandson of Ren Bishi, a leading military figure in Chairman Mao’s Long March, but in the oppressive atmosphere after the Tiananmen Square massacre, he and his wife, La Jia, decided to leave China for a new life in the west. He had told the Hong Kong border guard that he had “political problems” and wanted to leave China. He was asked where he wanted to go and told them “anywhere that speaks English.” (His English, many years after his move to Britain, remains sometimes eccentric: he refers to the prosecution as “the persecution”.)

In August 1992, he flew to London and contacted Philip Baker QC, who had a record of working with Chinese political refugees. Backing Wang’s application for political asylum, Baker wrote: “He has escaped from the country without permission, at a time when he was working on a top-secret military project.” Only a few weeks after arriving in London, Wang was granted political asylum, and the following year his wife was able to join him. To the intelligence services, he must have seemed a prime catch: a well-connected Chinese man who was also a computer expert. He has told the Guardian and senior MPs that he has assisted the authorities in many ways.

After arriving in Britain, Wang set up a company called Quantum Electronics Corporation, which he described as a laptop computer design, distribution and repair company. This ended in bankruptcy in 1999. In 2002, he set up another company, dealing in mortgages, which went bankrupt two years later, and led to bailiffs coming to his door to take goods in lieu of his massive debts. In 2005, he filed for personal bankruptcy, owing tens of thousands of pounds. His marriage to La Jia, with whom he had a daughter, ended. By the time of his arrest, he was in a relationship with another woman, and they had a son. His life was a mess both financially and personally. His chaotic and dishonest financial behaviour may well have worried his MI6 handlers.

It was in the early months of 2006, with his personal finances in chaos, that Wang helped himself to the mail that had accumulated in Chappelow’s letterbox and embarked on a spate of fraudulent transactions. As a thief, Wang was as sloppy and inefficient as he was in business, even using the stolen card to pay a small bill at the nearby Curry Paradise, not far from Chappelow’s house. It was his careless use of the card that helped the police to trace him, and led to his arrest in Switzerland in September 2006. He did not fight extradition, and was brought back to England and held in custody until his trial. The case against him rested almost entirely on his involvement with the bank thefts and fraud. There was no DNA or fingerprint evidence in either Chappelow’s or Wang’s house to link him to the murder. The cigarette butts and footprints found at the scene belonged to neither man.

During the trial, all that could be reported openly was that MI6 had demanded secrecy, that Wang was a “low-level informant” for the intelligence services, and that “part of his defence rested on his activities in that role”. Yet so anxious was MI6 to prevent the details of his defence from emerging in court that, in December 2007, just before Wang’s first trial opened, Jacqui Smith, then home secretary in Gordon Brown’s Labour government, signed a public interest immunity (PII) certificate – a gagging order – in order to prevent Wang’s evidence from being heard, on grounds of national security, and “to protect witnesses”.

Wang’s lawyers appealed to the European court of human rights in Strasbourg, on the grounds that Wang had been deprived of the right to a fair trial as a result of the gagging order. In response, in December 2013, William Hague – then the Conservative foreign secretary under David Cameron – signed another PII certificate, claiming there would be “a real risk of serious harm to an important public interest” if Wang’s defence was disclosed. Wang’s legal appeal was quashed in December 2015 by the supreme court, which ruled that there was a danger of the details of Wang’s defence being leaked by the European judges – whatever promises they might make to keep them secret.

Facebook Twitter Pinterest Police carrying out forensic investigations at 9 Downshire Hill after Allan Chappelow’s murder in 2006. Photograph: National Pictures

PII certificates are a long-established weapon in the government’s armoury of secrecy. The way they are open to abuse was first exposed by the Scott inquiry, which was commissioned in 1992 in response to the “arms-to-Iraq” scandal. Ministers had signed PII certificates to prevent evidence emerging about links between the directors of the weapons manufacturer Matrix Churchill and the security and intelligence agencies. MI5 and MI6 had used the company directors, who took frequent business trips to Iraq, to spy on what Saddam Hussein was up to. In a landmark judgment in 1992 on PII certificates, Lord Justice Bingham stated: “Public interest immunity is not a trump card vouchsafed to certain privileged players to play when and as they wish”.

Ministers were so desperate to prevent Wang’s evidence from seeing the light of day that, after Jacqui Smith’s gagging demand in 2007, they obtained a sweeping court order from high court judge Sir Duncan Ouseley, which ruled that journalists could not even speculate about what was said “in camera” (in a courtroom closed to the public and the press). When media organisations including the Guardian challenged this, Gavin Millar, QC for the Guardian, told Ouseley: “There have been plenty of trials in the past in which issues have been raised about national security material. It is extremely rare for such cases to be heard in camera.”

It was even suggested that the government could abandon the trial if it did it not get its guarantee of secrecy. Wang’s own barrister, Geoffrey Robertson QC, was strongly opposed to Wang’s case being held in secret, telling the court that Wang wanted the public to hear his defence, which was that his criminal activities – theft and financial fraud – were carried out in order to infiltrate a gang, and feed information to the “appropriate authorities”. The prosecution’s warning that, if the trial was held in the open, they might drop all charges and allow a potential murderer to roam the streets was described by Robertson as “forensic blackmail”.

Wang believed that the “trump card” had been used too casually by the government in his case. He said that he felt “totally abandoned” by MI6. In 2013, he wrote to the Guardian from Whitemoor prison in Cambridgeshire, stating the grounds for his claims of innocence: “I believe the only way to my freedom is to let the public know my defence. No cover-up.” In a later letter, he asked: “Do you remember ‘Dreyfus affair’ happening in 19s (sic) France? Cover-up never works but will backfire.”

On 24 January 2014, the Guardian ran a story headlined “The author, the dissident and a trial held in secret”. In it, we raised questions about the evidence, and the manner of its suppression. Within days, an email from a man called Jonathan Bean arrived. It said: “I read your article today with interest. I lived a few doors down from this back in 2006. The following Feb, I was in our house and heard a rustling in our porch. I opened the door to find a man with a knife going through our post. He pointed the knife at me and I shut the door. He then shouted through the door that he had been watching our house and knew that I had a wife and baby. He said if I called the police he would kill them. He waited in the porch for half an hour. I hid in the house but did not call the police until he had left. The police showed a strange lack of interest and just told me to change all my bank accounts. We then stayed with friends and moved to New York 2 weeks later. It is clear to me that there was a violent person or gang operating in the street, and the lack of police interest was very bizarre.”

Facebook Twitter Pinterest Allan Chappelow’s house on Downshire Hill, Hampstead, in 1948. Photograph: Rex/Shutterstock

According to Bean’s account, someone was burgling letterboxes in the same street, armed with a weapon, and threatening to kill if challenged. It is easy to imagine the effect that might have had on the jury in Wang’s first trial, which was split on the murder charge. Bean agreed to meet Wang’s lawyers in 2014, and his evidence was passed to the Criminal Cases Review Commission (CCRC), who investigated and referred the case back to the court of appeal in April 2016. The CCRC do not lightly refer cases: of 23,150 applications made to them in their 20 years of existence, only 636 have been referred to the court of appeal. (Of these, 421 have been granted.)

Meanwhile, another man, Peter Hall, on reading of the renewed interest in the case in the Camden New Journal in 2015, also got in touch with Wang’s lawyers. Hall said that, between 2000 and 2006, he was a regular visitor to a place on Hampstead Heath known as the “spanking bench”, and a participant in the sometimes violent sexual activities that went on there by night. At the time of the murder, in late 2006, he had seen Chappelow’s photo in the press, and had recognised him as a regular visitor to the bench, whom he knew as “Allan”. Hall took no action at the time, as Wang had already been arrested and the case seemed to be closed. But after reading the 2015 coverage, Hall contacted Wang’s lawyers and told them that on two occasions he had seen Chappelow depart from the bench with much younger men. This raised another possibility for Wang’s defence. If Chappelow did indeed meet strangers on the Heath, might he have brought one of them back to his house?

Both Bean and Hall agreed to give evidence at Wang’s appeal. In July last year, Wang’s case was heard by the court of appeal, led by Lord Thomas, sitting with Mr Justice Sweeney and Mrs Justice May. The appeal court thanked both Bean and Hall for their evidence but ruled that the trial jury had “clearly concluded that the web of activity undertaken by (Wang Yam) in relation to the deceased’s identity and accounts was so thoroughly interwoven with the murder itself that he, and only he, could have been responsible for the latter”. They said they could not find any respect in which the new evidence could have changed jurors’ minds.

After the failure of the appeal, Hall contacted us to say that he had wanted to spell out exactly the sort of risks that men ran on the Heath, but the court had only wanted to hear about his meetings with Chappelow. Earlier this month, we met him in a cafe in north London. He told us that he felt he had only been able to tell half his story.

Facebook Twitter Pinterest No 9 Downshire Hill in 2009. Photograph: REX

“I was going to point out how dangerous it can be on the Heath late at night, especially for people indulging in the activities I described,” said Hall, a slim-built man of 69 who lives in Hornsey, north London, and worked in advertising and local government until his retirement. The “spanking bench” has, he explained, a worldwide reputation, and attracts both those who like to be spanked and those who like to inflict punishment. A few years prior to Chappelow’s murder, another man Hall knew was beaten to death: “This man was a civil servant who was into heavy BDSM (bondage, domination, submission and masochism) and would ask men to beat him up. One night he met two men at the bench and was beaten so badly that he crawled into the undergrowth and died. Two men were subsequently convicted of his murder.”

Hall also mentioned the case of Mark Papazian, who was convicted in 2006 of the murder of a retired English teacher in his flat in Pond Street, two streets away from Downshire Hill. The jury at his trial was told that Papazian would search the Heath at night, looking for victims, because he fantasised about being a serial killer. In 2004, a man nicknamed “Gold Tooth” in the press, because of his distinctive capped tooth, was convicted of assault, theft and blackmail after a series of violent robberies on the Heath, and jailed for six years.

Hall, who said he had taken part in BDSM activities in the past, believes Chappelow’s death could well have been a sex encounter that ended in murder. He said that the wax burns and asphyxiation were indications of this kind of sexual encounter, and that he is surprised that the police did not look further into Chappelow’s private life. “Most of the crimes that occur on the Heath at night go unreported for various reasons,” said Hall. “This (Chappelow’s murder) was very unlikely to have been a burglary gone wrong.”

Despite what the appeal court said, the jury in the first trial “clearly concluded” nothing: they could not reach a verdict at all, and a small majority of them actually favoured acquittal. Their deliberations might have been very different if the evidence from both Jonathan Bean and Peter Hall had been available.

“When I submitted the application to the CCRC, I was confident that the fresh evidence – particularly that obtained by the Guardian – would lead to a referral back to the court of appeal,” said Kirsty Brimelow QC, who has represented Wang. “Evidence of a person stealing mail and threatening violence would have had a significant impact upon the jury. Also, the prosecution case focused on Mr Chappelow’s life as a recluse who never went out, and could not have met his assailant other than surprising a mail thief. Evidence of another side to his life would have challenged this focus, and in my view may well have changed the verdict. There always must be potential for unfairness with secret hearings.”

Geoffrey Robertson QC agrees. “Had the fresh evidence been available at the first trial, I do think it likely that Wang Yam would have been acquitted. I had, for example, raised the possibility of an assailant picked up on the Heath, but without the evidence that emerged years later that gave credence to the theory, consistent with some of the pathology, of a sadomasochistic ritual gone wrong. You cannot prove Wang Yam innocent – until someone confesses or they identify the DNA on the cigarettes – but doubts about his guilt are reasonable.”

The crumbling house in which Chappelow was murdered was later bought by developers, who demolished it and rebuilt a home in the Regency style, complete with an indoor swimming pool, private cinema and staff quarters. It went on the market last year for £14.5m, and has since been sold. This week, a black Range Rover stands in its driveway, there is not a leaf out of place in the garden, and the immaculately painted letterbox has the word “Post” painted helpfully on it. All traces of Allan Chappelow are gone.

Photographs in main image: Rex Features, family of Allan Chappelow, National Pictures, Julia Quenzler/Photonews, Met Police

Blood on the Page by Thomas Harding is published by William Heinemann

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