The case of murderer Joseph Kappen is renowned as being one of the first uses of familial DNA analysis in criminal identification. Familial DNA searching involves the use of DNA profiles of relatives, often from DNA databases or samples volunteered by individuals, to create new investigative leads to aid in the identification of the offender.
In 1973, three teenage girls (Sandra Newton, Pauline Floyd and Geraldine Hughes) were raped, strangled and dumped in an area of woodland near Port Talbot in South Wales. Despite a huge police investigation involving approximately 150 detectives, 200 suspects and dozens of buccal swabs, no arrests were made.
In 2000, Dr Jonathan Whitaker, a forensic scientist working with the Forensic Science Service, analysed the 28-year-old crime scene samples using the new Low Copy Number DNA technique, but no matches were found in the National DNA Database (NDNAD). The following year he attempted to search for potential relatives through familial DNA searching. As the murders had occurred in the 1970s, it was entirely plausible that the killer may have had children who could have their profile stored in the NDNAD. The DNA profile of car thief Paul Kappen was found, sharing 50% of the murderer’s DNA. It was later established that this was the son of the man responsible for the 1973 crimes.
However when detectives visited the ex-wife of Kappen, they were unfortunately informed that he had passed away ten years previously due to lung cancer. Armed with the recent information regarding Kappen’s son, they managed to persuade his ex-wife and her daughter to volunteer DNA samples. Using these profiles, it would be possible to obtain a full DNA profile for Joseph Kappen. The suspect’s body was eventually exhumed and analysis of DNA in the teeth and femur confirmed his identity. Although Joseph Kappen was never brought to justice, the case was finally closed.