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Episode 6: Under the microscope

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‘The Saturday Night Strangler’ aired last night, as part of Robbie Coltrane’s Critical Evidence 10pm and saw the future being used to catch up the past, so let’s take a closer look under the microscope.

A series of horrific murders, remaining unsolved for over 30 years. Yet it was the critical pieces of evidence, locked away in cold storage and police records, that allowed detectives to pick up the trail, using modern techniques unavailable at the time of the murders. Though ironically it was the vast influx of suspects that meant that it became almost impossible to tie the murders down to just one suspect, leading to the decades of stalemate.

It was due to the perseverance by forensic scientist Colin Dark, who had begun to develop a technique of testing seaman stains, to extract two separate strands of DNA, that of the victim and that of the attacker. But this practice had only been tested on recent sex cases, so any DNA would be fresh and therefore more intact. This is where the cold storage came into play as it had locked up not only the victim’s underwear, but the small amounts of the killers DNA.

Though this only took police so far, as it still meant they had to get five hundred names out of thirty thousand! They would then attempt to link that DNA with one of those names. Not an easy task, especially when there were only 4 officers working on the case. But just as the investigation seemed to have hit a brick wall, Joseph Kappen’s name cropped up, the only issue being that he was himself dead!

Only by exhuming his body were they able to finally lay the case to rest and the open questions in the minds of the parents of the 3 young girls, who had met such a violent end, at the hands of Kappen, vicious attacks on young and vulnerable girls, for no real reason other than the sick desires of one man, taking over 30 years to convict.

It raises several questions, most importantly regarding the time at which a crime is simply discarded, for instance the Zodiac killer in the US, a case which still remains unsolved today. At what point do police give up or with ever advancing forensic technology are we to expect more cold cases to solved in the coming years, finally bringing the perpetrators to justice. In the instance of Joseph Kappen, after 30 years a killer can be found. Regardless of them being alive or not justice must still beserved, even if must be posthumously. The threads, the fibers, the critical evidence is what finally trips up even the most elusive of criminals!