Detective Constable Joe Ryan arrived at a red-brick manor house in Hampstead, north London, early on the morning of October 31 2018. Ryan, a veteran money-laundering investigator with the Metropolitan Police, had obtained a warrant to search the property as part of an investigation into the activities of a 36-year-old woman named Jian Wen. A China-born British citizen, Wen had tried to buy a multimillion-pound property using bitcoin whose origin she couldn’t prove.
Walking up to the house, Ryan saw Wen sitting in a black Mercedes-Benz E-Class in the driveway. He tapped on the car window and told her he needed to search the house. Wen refused. Several officers surrounded the car, as Wen sat obstinately for five minutes. “It would be much easier if we had your keys to open the door, otherwise we’ll have to break in,” Ryan said. “If you want, we can arrest you,” warned another officer.
When she finally opened the front door, Wen went upstairs towards one of the bedrooms. Inside, police found Wen’s housemate, Yadi Zhang, in bed. She spoke little English. Over the next few hours, police seized laptops, notebooks and a pink USB stick stored in a metal tin. In Wen’s bedroom, they found £69,000 in cash. When police noticed Wen trying to delete apps from her iPhone, they asked her to hand it over. The case of another iPhone contained two €500 bills and a handwritten note with a list of passwords.
The true scale of what Ryan discovered would not become clear for years. The house and a safety deposit box searched the following day yielded more than 61,000 bitcoin, one of the largest sums of bitcoin ever seized by law enforcement, anywhere. The haul was valued at £1.41bn when unlocked in 2021.
By the time the police had the full picture, Zhang had disappeared. Wen’s housemate was a fugitive wanted in China for masterminding a massive investment fraud, they discovered. Wen was arrested in May 2021 and stood trial at Southwark Crown Court on 12 counts of money laundering and criminal possession last year. Legal restrictions have limited public reporting of the proceedings until now. This article is based primarily on evidence and testimony given in court.
Over five weeks, the trial provided a rare examination of the role of bitcoin in money laundering, showing how crypto can be used to squirrel away unfathomable sums. And how hard it can be for law enforcement to keep up. In court, Wen made a slight figure in an oversized blazer, wearing large glasses that filled her face. She had no supporters in the public gallery. Wen was flanked by four security officers as she was returned to Europe’s largest women’s prison every evening.
Wen, facing up to 14 years in prison on each of the dozen charges, pleaded not guilty. When she testified, she maintained, often to the point of tears, she had not known anything about Zhang’s crimes in China. Her barrister argued Wen was the victim of a “master manipulator”. With Zhang gone, he added, Wen was the police’s “consolation prize”. The Crown Prosecution Service’s barrister conceded the jury might find “there is no single piece of evidence that proves Ms Wen’s guilt”, but that the criminal origins of Zhang’s bitcoin “was staring her in the face”. There was little factual dispute about the evidence from either side. Instead, the jury was asked to judge whether Wen was Zhang’s trusted lieutenant or her victim.
Little in Wen’s background suggested she was a candidate to be drawn into a global crypto money-laundering scheme. Her parents were not wealthy, she told the court. Born in 1981, she attained a law degree and met a British man in China, whom she married. Wen was seven months pregnant when the family moved to the UK in 2007, settling in Halifax, West Yorkshire.
Wen’s marriage was not a happy one. Her husband was controlling and abusive, she testified. By 2010 they were divorced, and Wen lived in Leeds, working menial jobs. She later sent her son back to China for school. In 2017, she moved to London in search of better opportunities.
By September that year, Wen was living in a hostel and working in a Chinese takeaway. She had few belongings. Around this time, an advert on Chinese messaging app WeChat seeking a Mandarin-speaking assistant caught her attention. She called the number and was told to go to the Royal Garden Hotel on Kensington High Street. That’s where Wen met Zhang for the first time. “She was wearing a traditional Thai dress,” she recalled in her testimony to court. “She looked very young. Her skin was brilliant.”
Zhang claimed that she owned a jewellery business and had come to set up shop in the UK. She had a limp from a car accident and breathed heavily. Wen had no references, but Zhang offered to pay her £4,000 a month in cash to be her “carer and translator”, as she later described the job. Zhang told her new assistant that she needed new clothes, a bank account and a permanent place to live.
Zhang’s real name was Zhimin Qian. She was on the run from the Chinese authorities. Between 2014 and 2017, she orchestrated a £5bn investment scam in China through a company called Tianjin Lantian Gerui Technology Company. Some 128,000 investors were ensnared, and more than a dozen people in China have been convicted in relation to the scheme, the court heard. (Wen was not accused of being involved.) Having converted much of her investors’ cash into bitcoin, Zhang fled with the funds on a Lenovo laptop, one of the items later seized by UK police. She’d arrived in London with a new name and a St Kitts and Nevis passport with a birth year of 1990, making her improbably young. (She was really born in 1978.)
Within days of meeting Zhang, Wen was dealing in fraudulent documents and dizzying sums of money. She obtained a fake gas bill Zhang could use as proof of address on a bank application, the court heard. In September 2017, Wen negotiated with estate agent Chestertons for the tenancy of the Hampstead mansion, which cost £17,300 a month. She and Zhang were joint tenants. She told Chestertons she worked for Zhang’s jewellery company.
In October and November, Wen drafted a letter to her bank to try to explain £40,000 that had showed up in her account. In the letter, which Wen said was never used, she falsely claimed a boyfriend had sent the money for “home improvements”. She took two trips to Thailand, purportedly to pick up jewellery from Zhang’s boyfriend. Each time, she returned with a new laptop. At some point, Wen also took delivery of £200,000 in cash at the Hampstead house. In court, she could not recall who delivered it.
There were signs that Wen felt uneasy about aspects of her new job. In December, she asked an accountant she knew if she should let a “friend” funnel £2mn from the sale of bitcoin through her personal bank account. Would there be tax issues, she asked. No, he replied, but “personally, I wouldn’t do it in case they investigated me for money laundering.” Wen told the court that she took the accountant’s advice.
Still, in general, she trusted Zhang, Wen said. She didn’t think to question her. Zhang’s sensibilities seemed in line with cryptocurrency circles, Wen told the court. Zhang had told her that her wealth came from legitimate sources, such as jewellery and bitcoin mining. “I did not know she had involved anything in China at all,” she testified.
Zhang was soon asking Wen to facilitate a more complicated task: buying property. Wen enlisted the property advisory London Wall. Lev Loginov, the company’s co-founder, found a £23.5mn mansion with eight bedrooms and an indoor swimming pool on Lyndhurst Road, also in Hampstead. He introduced Wen to a property lawyer, James Liffen of Mishcon de Reya, a top London firm.
The transaction would be complicated. Wen told Liffen that Zhang wanted her to be the sole owner of the house and transfer ownership after a year. In an email, Liffen enquired about the unusual arrangement. “Is it for confidentiality reasons?” he wrote. Wen replied she didn’t know.
Wen told Loginov over WhatsApp they wanted to pay for the property with bitcoin, but Zhang couldn’t provide details about the source of the funds. “If you can solve this problem for her, then she’d like to purchase it,” Wen told Loginov in January 2018. “Yes,” he replied. “Let’s meet and talk.”
Loginov introduced Wen to Anwar Sioufi, who ran Exmoor Partners, a Financial Conduct Authority-registered brokerage. Exmoor would convert the bitcoin to cash and provide a report that would purport to verify the source of funds for the property purchase, the court heard. The contracts with Exmoor and Mishcon were in Wen’s name, just like the house. In February, Exmoor converted £850,000 worth of bitcoin and sent the funds to Liffen’s law firm as a deposit for the house. One step closer to converting the bitcoin.
The criminal appeal of cryptocurrency is obvious. Despite enthusiasts lauding the transparency of digital currency, it is easy to move large sums without detection — a laptop full of bitcoin draws less attention than a suitcase of cash — and can’t be blocked like bank transfers. Since bitcoin’s creation in 2009, regulated financial institutions have viewed the sector warily, worried about money-laundering risks. The “relatively anonymous nature of bitcoin makes it an attractive means for anyone who wants to hide the source of illegally obtained money”, said the judge in Wen’s case, Alexander Milne KC. He hastened to add that “doesn’t mean if you own bitcoin you’re a crook”.
Zhang did not stay in London long. She spent much of 2018 travelling across continental Europe. Wen typically tagged along. The pair often travelled by car, which Zhang wrote would minimise border checks in a diary seized by police. Their travels were documented in countless photos of the two, each always standing alone, never both in the same picture. Before they went to Sweden in April, Wen searched online for “china extradition treaty sweden”.
Back in London, the Lyndhurst Road deal collapsed when the seller asked for more money. Wen and Zhang’s property advisory found a second location worth £12.5mn in Totteridge Common, London, with eight bedrooms, a home cinema, gym and sauna. But by then, the women’s activities had begun to raise flags. Alarmed at the unexplained sums pouring in, Wen’s bank closed her account. She attempted to open a new one at other banks. Zhang told her to try Citibank. “You open an account first, test the water for me. It is said they like big notes, not so strict,” Zhang wrote in a text. Yet €276,000 of electronic transfers later, Citibank also shut down Wen’s account.
As the Totteridge Common deal progressed, Liffen pressed Wen for more information about the source of Zhang’s crypto. Zhang had said she had mined her bitcoin but had not kept any records. Liffen wanted to see addresses for the bitcoin on the public blockchain database that records transactions, the court heard, allowing his firm to trace the history of the money that was going to be used for the purchase. Zhang, through Wen, refused, stalled and produced the wrong addresses. Then in July, Wen asked Sioufi of Exmoor Partners to convert almost £1mn of bitcoin for the Totteridge Common deal. He ran off with the money, the court heard. Mishcon’s reticence gummed up the Totteridge Common purchase as London Wall declined to sign up another broker until the law firm gave the all-clear.
Wen eventually provided the correct blockchain address to Liffen. But the blockchain evidence didn’t match Zhang’s story. Mined bitcoin would come newly minted from just a few sources, but Zhang’s bitcoin had come from hundreds of sources, including crypto exchanges. In September, Wen and Zhang had another scare. They were stopped by immigration in Dublin because of issues with Zhang’s visa. Wen had €30,000 in cash on her. The jury was shown a photo of Zhang taken by Irish officials. It showed a woman with a round face, double chin, small glasses and short black hair. The Irish authorities sent Zhang back to Vienna, where she’d come from. Wen returned to London. Her son had arrived back from China to attend a British private school, paid for by Zhang.
Shortly after the Dublin incident, Wen created what would become a pivotal piece of evidence. She photographed the pages of a notebook with details of passwords for Zhang’s bitcoin wallets and stored them on a pink USB stick.
The jury were not told how exactly Detective Constable Ryan caught wind of Wen’s activities. But on October 10, he sent Wen an email informing her he had obtained a freezing order on the £850,000 her law firm still held. At the time, Wen assumed Mishcon had tipped off the police. “Fxxx”, she wrote to a London Wall employee, censoring herself.
A few weeks later, Ryan tapped on the window of her Mercedes. During a voluntary interview with the police, Wen provided a written statement describing herself as Zhang’s “carer and translator” and claiming to know “very little” about bitcoin. By then, a criminal defence lawyer working for Zhang was battling the police in court to get back her seized possessions. Over WhatsApp, Wen and Zhang discussed collecting evidence to prove where the money had come from. “We have to show something,” Wen wrote to Zhang in August 2019.
Despite the police attention, Wen continued to work for Zhang. Through 2019 and 2020, she helped Zhang convert bitcoin by trading with strangers in London. Zhang transferred the coins, and Wen picked up the bags of cash. In messages Wen exchanged with one buyer, she discussed avoiding locations covered by CCTV. Wen handled more than £400,000 in cash from these trades in this period, the judge estimated.
At the same time, Wen began looking for property in Dubai and enlisted the help of a broker, Michael Burke, who ran a real-estate business called Arabian Escapes, the court heard. When Wen completed the registration forms, Burke told Wen not to worry about how she described her source of funds. “Between you and me. What is the real source and I will think of something,” Burke said in a message shown in court.
After Wen assured him the bitcoin wasn’t linked to any crime, Burke helped her buy two apartments in Dubai in late 2019. He also helped Wen sell more than £2mn worth of bitcoin through his companies MJB Holdings in the Seychelles and Outsourced Serviced Solutions in Switzerland, the court heard. Much of the proceeds were deposited on prepaid cards Burke arranged. Wen sent the cards to Zhang.
In August 2020, the police returned to the Hampstead mansion for a second search. This time, Zhang was not there. Wen told the court that the last time she saw Zhang was at the house later that month, August 25. They were terminating the lease. Wen kept what remained of the £40,000 deposit and the Mercedes. Before Zhang was due to be interviewed by the police, she disappeared. “I have heard nothing since from her,” Wen told the court.
By May 2021, Wen was living in a two-bedroom flat in south London with her son and working in a restaurant when Ryan turned up a final time. After searching her flat, he arrested her. A later search turned up a handwritten note: “if they break the btc codes, I’m dead”. When asked to explain what it meant in court, Wen rambled, seemingly in anguish. She said the pressure of the investigation had made her suicidal.
That same month, the police began unlocking Zhang’s bitcoin wallets, finding at first sums totalling in the hundreds of millions of pounds. In mid-July, they opened the two largest wallets and found £1.2bn worth of bitcoin. The jury wasn’t told why the police investigation had taken almost three years. But since the initial 2018 search, some bitcoin had been funnelled away. In the early hours of the morning of May 30 2021, 4,000 bitcoin — more than £100mn worth. Nearly 500 more was siphoned a few days later. Wen didn’t do it, her barrister said. The court heard no evidence about who did.
Last March, the jury finally reached a verdict after 11 hours and 13 minutes of deliberation. The judge had given them permission to reach verdicts with a majority of 10 rather than unanimously.
In the courtroom, the clerk asked Wen to stand. The jury foreman, a smartly dressed man in a suit, also stood. On the first charge, no verdict. On the second, not guilty. The third, no verdict. Wen didn’t react, her lips tightly pursed. Then on the remaining counts, the foreman’s quiet but steady repetition of the same words: “Not guilty. Not guilty. Not guilty.” The jury could not reach a decision on two charges. On all the others, Wen was acquitted.
Wen covered her face with her hand. Ryan and the other police officers in the gallery appeared stunned. One of the jurors clasped her hands together and closed her eyes, as if in prayer.
The verdicts capped a string of failures for the Crown. In the years the police had investigated the case, an international fugitive had escaped their grasp and large amounts of bitcoin had been lost. Mid-trial, the judge tossed out two possession charges relating to the highest-value wallets. The passwords for those were in code. Mark Harries KC, Wen’s barrister, successfully argued there was no evidence that she ever knew the uncoded versions. Now the jury, at least 10 of them, had dispensed with much of the remaining case.
Harries, in his closing speech had urged the jury to look past the “glitzy” prosecution, even past Wen’s own questionable conduct, and to instead focus on whether the evidence actually proved that Wen knew or suspected Zhang’s bitcoin had criminal origins. Wen had been “a nobody”, Harries said, who was “desperate to drag herself from her old life”. Might she have simply trusted Zhang, “who’d plucked her from the kitchen and put her up in a £4mn house in Hampstead?” he asked. “Might she be not guilty of any of this?” On most counts, the jury must have found itself wondering the same thing.
A year later Wen was still in prison, her routine unchanged. Each day this February, as she had last February, she was brought from a cell to Southwark Crown Court to stand trial on charges of laundering Zhang’s bitcoin. The CPS retried the two counts on which Wen was not acquitted. By the time the second trial came around, prosecutors added a third charge on another bitcoin wallet that was newly identified. Altogether the amount of money Wen was now accused of laundering totalled nearly £1mn.
In March 2023, Harries asked the judge to grant bail on the grounds that she had never tried to flee at any point in the investigation. What was left of the case would imply a significantly reduced sentence, even if she was convicted. The request was denied. Wen’s incarceration, since March the prior year, created a flight risk. “She knows what it is to be in custody,” Judge Milne noted.
During the second trial, Wen looked ill, often coughing. The proceedings were a near facsimile of the first trial. Gillian Jones KC for the prosecution recounted the whole story again. Harries for the defence again told the jury to look past the drama of the case. Wen again broke down on the stand, tears flowing in front of a new jury.
On Monday, that jury found her guilty on one of the three money laundering charges by majority verdict. On the other two the jury could not reach a verdict. Wen will be sentenced in May.
Kadhim Shubber is the FT’s UK news editor.
Eri Sugiura is an FT reporter. Additional reporting by Abby Wallace, Eleanor Olcott and Euan Healy
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