Don't flee the scene of a road accident or mix illicit chemicals in your backyard were the messages Garda forensic lab scientist Ms Annette Forde gave students at a lecture yesterday.
With its high-tech equipment, the lab helps to solve crimes from burglary to arson to sexual assaults, Ms Forde said. Lesser offences such as traffic accidents are also put under the microscope.
One case involved a father and son preparing a batch of the hallucinogenic drug mescaline in their yard, Ms Forde said.
"They had been noticed buying an array of unusual chemicals. And when the gardai checked out the shed, they found loads of chemicals - and written chemical equations - and our lab determined they were creating illegal drugs."
Although Ms Forde said the lab was impressed with the teenager's chemical knowledge, she noted that "his crime didn't pay. He was caught, fined and now has a serious criminal record."
The lab is a central element in prosecuting drug crimes, she added. "Every case that goes to court goes with a certificate from our lab that the substance in question is indeed prohibited."
The biology section of the lab, commonly referred to as the "blood-and-guts" division, uses techniques such as DNA testing to assist the i Garda in solving murder and assault cases. "DNA sampling and testing is constantly becoming more powerful. We can now use a tiny sample such as genetic material left on a steering wheel and be accurate," she said.
Her chemistry section works with trace evidence left at crime scenes, from marks such as tyre impressions and footprints to particles such as paint, glass and fibres.
"We linked one suspect to a crime solely from one muddy print on an envelope on the floor. Shoes have a unique ID," she explained. Car paint does as well, and the lab can test a small speck of foreign paint from a car that was struck and narrow down the offending car to a specific model and year.
Justice was served for a man found dead by the side of the road when the lab linked particles of glass found on his sweater to a car under suspicion, Ms Forde said. "Microscopic fibres from his jumper were also lifted by Sellotape from the headlamp, and we knew we had solved that hit-and-run."
In arson cases, gas chromatography is used to identify the type of accelerant used, according to Ms Forde. "By analysing the vapours, we can identify if it was petrol or paraffin oil or something else feeding the fire, and that helps to associate suspects with the crime."
Ms Forde said that today's forensic technology is vastly improved from 20 years ago. "The miscarriages of justice that occurred in the Birmingham Six and the Guildford Four cases would not happen today. It was not necessarily bad science, but bad interpretations of the results," she concluded.
