Geraldine Palk

Forensic Science Service (FSS) scientists used an ‘intuitive approach’ to obtain a murderer’s DNA profile after all evidence from the crime had seemingly gone.

The FSS’s specialist DNA unit used DNA Low Copy Number to obtain the profile of Geraldine Palk’s suspected killer from a plastic tube used to store the medical swabs taken from her body a decade earlier.

All other evidence in the case was apparently used up in previous tests undertaken in 1991, so scientists decided in 2001 to try and examine the plastic ‘sleeve’ that the swab had been kept in.

They hoped material from the cotton wool swab had been left on the inside of the tube when the swab was placed inside. The tip of the wooden swab stick was also tested in case genetic material from the original cotton wool swab had soaked through.

Remarkably, a full DNA profile was obtained and, when it was searched against the National DNA Database®, it matched with Mark Hampson, whose profile had been put on the database after his arrest for another crime.

Hampson was found guilty of murder at Bristol Crown Court in November 2002 and jailed for life.

Dr Jonathan Whitaker, from the specialist DNA unit, said: “We approach each case on its own merits and in this instance we were able to plan out a forensic strategy with South Wales Police to evaluate the potential for DNA testing of remaining items with the DNA technologies of today.

“This included testing items which would never have been considered before using an intuitive approach which took into account where we might expect to find remains of the original genetic material from the offence.”

DNA profiling was in its infancy at the time of Geraldine’s murder. Even so, FSS scientists did obtain a profile that led to an intelligence-led screen to be set up in 1991.

However, no suspect was identified and, because of the nature of the early DNA profiling techniques, all samples from the crime were used up.

The original DNA profile became effectively obsolete for intelligence purposes as technological advances continued over the next few years. By the time the National DNA Database was set up in 1995, different areas of DNA were being looked at so the original profile could never be checked against it for a possible suspect.