a cigarette butt has been key to solving a crime committed 30 years ago in Scotland, thanks to new DNA techniques that have made it possible to find the murderer and sexual attacker of a woman.
Mary McLaughlin, 58, was murdered in Glasgow in the early hours of September 27, 1984. Her body was found strangled in her home by one of her eleven children, Martin Cullenfive days later.
Detectives gathered more than 1,000 statements in the following months, but the search for Mary’s killer came to nothing and a year later, police told the family that the investigation was closed.
Now, a documentary of the BBC titled Murder Case: The Hunt for Mary McLaughlin’s Killerrecounts not only the details of what happened that night, but also how the case was resolved.
In 2008, four independent investigations had failed to produce a profile of the suspect. The fifth review was carried out in 2014 and the final breakthrough was made possible by a new DNA profiling facility at the Scottish Crime Campus (SCC).
Previously, experts could observe 11 DNA markers individual, but the latest technology is capable of identifying 24. This dramatically increased the chances of scientists getting a result from smaller or lower quality samples.
Samples collected in 1984 included strands of Mary’s hair, fingernail residue and cigarette butts. The breakthrough finally came with a cigarette butt an Embassy brand cigarette which was unlit in an ashtray on the coffee table in the living room, which was very interesting, because it was not the brand that Mary smoked.
And indeed, the analysis of the butt gave a complete male DNA profile. It was identified Graham McGilla man with serious convictions for sexual assaults.
But the investigation found a new obstacle: at the time of the crime, McGill was serving a sentence, and had not been released. until nine days after the day of the murder.
They continued searching for evidence and found McGill’s DNA on the belt loop of the robe used to strangle Mary McLaughlin. As if that were not enough, they were also found traces of McGill’s semen on the woman’s dress.
All that remained was to figure out how to resolve the contradiction that McGill was in prison at the time of the crime. It was not until an exhaustive search of the National Records of Scotland in Edinburgh that they discovered that on September 27, 1984, McGill I was on weekend leave.
Graham McGill was arrested on December 4, 2019. He committed the crime when he was 22 years old and 57 years old. McGill was eventually found guilty after a four-day trial in April 2021 and jailed for a minimum of 14 years. The crime was thus solved.
#Cigarette #butt #helps #solve #30yearold #murder #mystery
