In the summer of 2018, the private investigator Simon Davison got a call from a woman who said her ex-boyfriend had stolen £10,000 from her. Carol (not her real name), a traffic manager at a local council, was not a typical client for Davison. As the director of investigations at AnotherDay, a crisis consultancy in London, Davison usually works for wary companies and wealthy individuals. A former police detective, Davison has recovered stolen cryptocurrency, uncovered secret properties owned by bankrupt business people and tracked down fraudsters to Cyprus.

Davison’s speciality is private prosecutions, a little-known area of law that allows victims to pay for justice. These cases are heard in the same courts used by the Crown Prosecution Service (CPS), the public prosecutor for England and Wales, and they can carry the same amount of prison time for suspects. “We really mirror the process between the police and the CPS,” Davison said. The difference is that the police are agents of the state, whereas people call on Davison when the state fails to help.

Carol’s ex-boyfriend, Jiro Wilson, had persuaded her to lend him money to finance a company he was setting up. In exchange, Wilson promised her shares in his fledgling firm. “Looking back, I could see how stupid I was to believe him,” Carol later recalled in a witness statement. “He would often call me paranoid, and certainly made me feel this way when I suspected [he was] seeing other women.”

One evening, while surreptitiously scrolling through Wilson’s phone, she saved the numbers of other women in his address book, and began texting them in secret. To Carol’s horror, three women told her that Wilson had also “borrowed” thousands of pounds from them, too. Carol set up a WhatsApp group, and arranged to meet the women at one of their homes in Exeter. The four women discovered that each had been duped in the same way. “He was a disgusting narcissist,” one of them told me. In total, Wilson had stolen £46,000 from them, promising they would reap the benefits of investing in his company. He spent the money on escorts, eating out and motorbikes.

Carol reported Wilson’s theft to the police, who referred her to the national fraud hotline, which gave her a reference number and never contacted her again. The three other women also failed to interest law enforcement in their case. More than getting their money back, the women wanted justice. One contacted a solicitor in Exeter called Jeremy Asher. “It was very obvious that this was a substantial fraud committed by a very devious, calculating manipulator,” Asher recalled. “But the police weren’t interested.” Asher advised the women to bring a private prosecution. Doing so would be expensive – in the tens of thousands of pounds – but their case was so strong that Asher said the court would probably reimburse their costs. So the women cobbled together the money, and on Asher’s recommendation, Carol contacted Davison, the private investigator.

As he dug into the case, Davison found that Wilson also appeared to have fiddled his VAT returns. The judge who heard the private prosecution in December 2020 decided Wilson’s offences were potentially so serious that the CPS should take over the case. The CPS passed the case to the police, who discovered that Wilson had submitted nearly £250,000 in fraudulent VAT returns, and had stolen a further £50,000 from a government loan scheme. On 13 June 2023, Wilson pleaded guilty to seven counts of fraud at Exeter crown court. A judge sentenced him to six years in prison and described him as a “dishonest parasite”.

Had the police taken Carol and the other women’s initial allegations more seriously, a private prosecution would never have been necessary. But their experience is not uncommon.