One of the earliest advocates of forensic science in Ireland, Supt George Lawlor, had a story he liked to tell. In 1907, the Dublin administration decided it was time to start using the then cutting-edge system of fingerprint identification. Warders from the country’s prisons were told to start fingerprinting their prisoners. These fingerprints were then sent to Dublin to be classified and stored.
After a year, the civil servants began noticing that many of the prisoner’s fingerprints were coming back were identical. Panic spread throughout the administration; perhaps fingerprints weren’t unique at all and the whole system was worthless?
However, as Lawlor's biographer Tom Reddy writes, it soon emerged that one of the warders believed the idea of fingerprints being unique was a load of nonsense. So, to save time, instead of getting each individual prisoner's fingerprints, "he simply inked his own digits and sent them off to Dublin".
Thankfully, Ireland has come a long way since then in the area of forensics and for this, Lawlor deserves a share of the credit.
In the early days of the State, he pioneered methods of blood and fingerprint evidence and even came up with a way of identifying corpses by examining their hands for tell-tale marks which would link them to their profession. For example,clerks would have small callouses on their index fingers while washerwomen would have soft swollen hands.
Today forensics is usually a byword for DNA evidence. The country's laboratory, Forensic Science Ireland (FSI) operates the very latest form of DNA analysis, which it has been used in many successful prosecutions over the years, most notably in rape and murder cases when accurate DNA-matching is vital in putting a suspect at a crime scene.
DNA analysis is relatively cheap, easy to explain to a jury and, thanks to TV shows like CSI, viewed as nearly above question in its reliability. However, DNA is not infallible and there is some evidence to suggest that because of its many strengths, it is being used at the expense of other, more traditional forms, of forensic analysis.
“I see the main problems as over-reliance on reporting simple DNA profile matches without evaluation of their meaning in context, and underuse of powerful forms of subjective forensic evidence which require experience, such as blood-pattern evaluation,” says Dr Duncan Woods, a UK forensics expert.
Blood pattern
Blood-pattern evidence is a powerful tool that can show what happened at a crime scene in a way which DNA cannot. For example, during Eamonn Lillis’s 2010 trial for the killing of his wife, a forensic scientist was able to show that blood found on boots recovered from Lillis’s wardrobe got there by travelling through the air, indicating they were worn during the killing.
To use another example offered by Dr Woods, blood-pattern analysis could be used to prove or disprove a defendant’s claim that he was simply intervening to stop a fight. A drip pattern would support this claim, while a larger stain might discredit it. “In these circumstances, DNA profiling a stain or two may be evidentially pointless, but consideration of overall blood patterns could be crucial,” he says.
Blood-pattern analysis is particularly useful for challenging a suspect’s account of their movements at the scene. According to Dr Woods, it can tell a jury or investigator if a victim was standing or lying down when they were hit, if they tried to defend themselves and if they were dragged elsewhere afterwards.
Dr Woods works for Keith Borer Consultants, an independent forensic consultancy which deals with many Irish cases. He believes that despite a wealth of expertise within FSI, blood-pattern analysis is underused here or not used to its full potential.
“The scientists at the lab in Belfast are frequently called out to scenes to assess the blood-pattern evidence; this is not routine for the staff at the lab in Dublin,” he says. “In addition, with reports from the FSI Dublin, it is common to see bloodstains described at a spot or smear, but nothing to consider where the evidence supports that the wearer kicked or punched.”
According to Dr Woods, while FSI staff have ample training and expertise in such analysis, “it just never seems to find its way into statements”.
FSI's director of chemical sciences Dr Tom Hannigan told a recent conference that he would not say there was an over-reliance on DNA, but there was an expectation at the same time to provide a high quality DNA service.
“In other countries, particularly the UK, where the forensic science services have been privatised, there has been a loss of expertise and a loss of skills and lack of investment in the more traditional scientific techniques. We are doing our best not to go that way,” he said.
Subjective methods
One of the problems with subjective forensic methods such as blood-pattern analysis is that they take time, money and expertise. This is a problem in a country where the head of the forensic science lab publicly states they are in “crisis”.
FSI director Dr Sheila Willis told an Oireachtas committee in March that she did not have nearly enough staff to meet demand and that FSI facilities were 20 years out of date.
The potential dangers of over-reliance on DNA were shown recently during the trial of Mark Nash for the murder of two women in Grangegorman. The trial heard that 14 DNA contamination events occurred at the national lab in 2011, 22 in 2013 and 31 in 2014.
In one particularly worrying incident from 2013, DNA from one case was found on a bloody lamp which was evidence in a completely separate prosecution. The cross-contamination occurred when scientists were examining the two items at the same time, on the same surface.
The defence used these failures to argue something similar could have happened in the Nash case. They suggested DNA from the murder scene contaminated Nash’s jacket when both items were examined in the lab within a six-week period. The court also heard there was no written cleaning procedure in place for the lab at the time.
However, even if the jury did accept there were forensic failures in the Nash case, there was ample additional evidence which allowed it to return a guilty verdict.
However it doesn't take a huge leap of imagination to envisage a situation where such failures could lead to a guilty person walking free. The even worse scenario of an innocent person going to prison is mitigated somewhat by the Frederick Howe case of 2003 in which the Central Criminal Court stated that DNA evidence alone was not enough to convict on.
Like many of the problems in the criminal justice system, the issue seems to be a lack of resources. Dr Hannigan pointed out that it was difficult to deliver a diverse and modern forensics service while working out of the non-purpose built 1970s-style office block which serves as the headquarters of FSI. It is clear that immediate investment is needed both in DNA-testing and in other forms of forensics to avoid a catastrophe. In the meantime perhaps we can still learn a few things from the late Supt Lawlor.