While walking her dog on Wimbledon Common in 1992, Rachel Nickell became the victim of a vicious sexual assault and was stabbed 40 times before her attacker fled the scene. A passer-by found Rachelʼs body with her two-year-old son Alex clinging to her side, trying to wake her up. Police mounted a huge investigation, but had few clues to follow up. After a suspect emerged in Colin Stagg, they mounted an operation involving an undercover female officer who feigned a relationship with Stagg for five months, hoping to glean evidence from him. Although the police gathered enough information to send Stagg to trial in 1994, a judge at the Old Bailey threw the evidence out, believing it to have been gathered by “deceptive conduct of the grossest kind”. By 2007, Stagg had received over £700,000 in compensation. After new DNA evidence came to light, a prisoner named Robert Napper, who was already serving a sentence for another killing, was found guilty of Nickellʼs murder. Colin Stagg received a full apology from the police.