THE DNA at the crime scene was always going to be the police’s best hope of catching the real killer after it was used to categorically rule out Sean Hodgson.

After it produced no direct matches to a complete profile, scientists had to cast their net wider to see whether forensic science could give the police the breakthrough they needed.

They employed cutting edge science to determine whether anyone on the National DNA Database had DNA that was so similar it was likely that they could be related to the then unknown killer.

Daily Echo: Click below to see a video of today's headlines in sixty seconds

Dr Colin Dark, of the Forensic Science Service, said: “When we don’t get a complete match we then look for relatives.

“Parents can provide a half DNA profile match, but we can also look for siblings or other relatives who have similar DNA, which is a bit more difficult, but those matches are best described as a near miss.

“We can then further narrow down that list of potential relatives by applying geographical and age filters that can help police with their research.”

While the work was going on in the labs the police were revisiting the original case files that were remaining, and narrowed down their list of suspects from the many who gave confessions or who were investigated at the time.

Watch videos of:

• Teresa's parents give their reaction
• David Lace's Confession Statement
• The 1983 Investigation
• Who was David Lace?
• The 2009 Investigation

Det Chief Insp Phil McTavish said: “When we combined our research with the admission that he made to police, the fact that he killed himself and the forensic picture that was building up, it made him a stronger suspect.”

Meanwhile, the Forensic Science Service had found a match that was to prove crucial to the investigation. A sister of David Lace came up as a ‘near miss’ match to the killer’s profile.

Although Lace’s natural parents were dead, officers were able to get hold of histology samples from medical records that also gave further proof that the killer was David Lace.

It was working through all this information that led police to finally declare him a prime suspect and as a result they were granted permission to exhume his remains from Kingston Cemetery in Portsmouth, where he had been buried since 1988.

Det Chief Insp McTavish said: “High quality DNA material was extracted in the process and used for comparison. We are fully satisfied that the person exhumed was David Lace and identification was indeed proven. It is therefore confirmed that the DNA profile of David Lace is a complete match with the DNA profile from the original crime scene with a match probability of one in one billion.”