Strange story about murderer

A woman's body was found in London, England. The DNA test results confused the police, because the suspect seems to have died a few weeks before the victim. This is one of the strangest cases that British forensic expert Dr. Mike Silverman has witnessed in his life.

The mystery of the culprit died before the victim . a few weeks

According to Dr. Silverman, the case was a mystery in real life: A woman was brutally massacred in London. Biological materials found under the victim's fingernails imply, she may have scratched the attacker right before she died. A sample of evidence was analyzed, then compared with the UK national DNA database and quickly resulted in a coincidence.

The shocking problem is, the evidence helps identify a woman who was murdered three weeks before the death of the victim. Two murders occurred in different areas in London and conducted by separate investigation teams.

Since there are no signs of contact between the two women and there is no proof that they have ever met, the authorities say, most likely, the evidence samples have been mixed or unclean. at a certain meeting point between them - forensic laboratory. A senior official in charge of the investigation has made a formal complaint.

The incident happened in 1997. At that time, Dr. Silverman was in charge of the British Forensic Authority, so he was tasked to find out if any errors had occurred in the forensic laboratory.

At first, Mr. Silverman speculated, perhaps, the second victim's nail model was mistakenly labeled and actually belonged to the first victim. However, when considering the sample, he found this speculation to be wrong.

Dr. Silverman then thoroughly examined every forensic laboratory file to see if the samples were accidentally mixed in some way. Eventually, he discovered, both bodies underwent autopsies at the same morgue, although they were taken there weeks apart and conducted by various autopsy groups.

Eraser confused

Forensic autopsy, which is carried out in case of murder or suspicious death, is done more thoroughly and elaborately than a normal autopsy. In particular, experts will collect blood and viscera samples to check for toxicity, collect and analyze things inside the stomach as well as extract and cut the nail of the corpse.

When researching the morgue's records, Mr. Silverman suddenly found the key to uncover the mystery of the incident. It turns out, the body of the first victim was stored in the air conditioner for weeks while the police conducted an initial investigation. The body was removed from the freezer so that the pathologist cut the nail samples before the body of the second victim was transferred to the morgue.

The next day, it was the same nail cutter that was used to cut the second victim's nail sample. Although the scissors were disinfected between two uses, but due to negligence, the genetic material from the first victim remained "through" through the disinfection process and transferred to the second victim's fingernails, leading to Strange DNA analysis results.

The test results for the morgue's nail test scissors even revealed, not only 2 but 3 separate DNA patterns existed on it. DNA contamination is also detected in many other morgue tools, such as an autopsy but does not cause problems because they are not used to extract DNA samples.

Mr. Silverman immediately sent an urgent memorandum to all investigators, forensic experts and morgue throughout the UK, stating the issue and requirements, in the future, all the manicures needed. must be done with disposable scissors and they are then put into the evidence bag with the nail model to verify this. The process is still being followed up to now.

Modern challenges

Modern DNA analysis is so sensitive that defilement is a big problem due to the risk of criminal investigations taking place in the wrong direction. In 2007, in Germany, DNA traces belonged to an anonymous woman found at the scene of a police murder. When compared to the German database, identical DNA samples seem to have existed in the scene of five other massacres in Germany and France along with the scene of numerous car theft and theft. The total DNA of that woman was recorded in the field of 40 separate cases.

It took the German authorities two years to find the culprit, only to discover that the DNA pattern actually appeared in the gauze used by hospital investigators to collect samples in the field. These swabs were accidentally produced by a woman who worked for the company.

Over the years, DNA has been considered the ultimate anti-perpetual weapon, helping to successfully smash the culprits of the cases with fewer traces. However, Mr. Silverman said, in many ways, DNA analysis can become a victim of its own success, if the process of collecting, processing and analyzing is not conducted carefully, in order to eliminate abandon the possibility of confusion or uncleanness, or lack of evidence that reinforces its direct relevance to the case.