Judge to rule on controversial evidence in Massereene trial on Thursday
A JUDGE in the trial of two men accused of murdering two soldiers will decide whether to allow controversial forensic evidence on Thursday.
Mr Justice Anthony Hart has been hearing legal arguments on the admissibility of the DNA test.
The prosecution claims the samples connect Colin Duffy and Brian Shivers to the gun attack on Sappers Mark Quinsey and Patrick Azimkar outside their Army base in Antrim.
The defence believes the computer-based assessment of US expert Dr Mark Perlin has not been properly recognised by other scientists.
Prosecution barrister Terence Mooney QC told Antrim Crown Court: "It is admissible on the basis that it is derived from scientific evidence which is reliable, proven and advanced by an expert in the field.
"It is therefore evidence upon which the court can place confidence and give weight."
Sappers Quinsey, 23, and Azimkar, 21, were shot dead by the Real IRA as they collected pizzas with comrades outside Massereene Army base in Antrim in March 2009.
Duffy, 44, from Lurgan, Co Armagh, and Shivers, 46, from Magherafelt, Co Derry, deny two charges of murder and the attempted murder of six others - three soldiers, two pizza delivery drivers and a security guard.
Dr Perlin's system strongly linked the two men to the getaway car used in the attack.
He tested DNA from a seatbelt buckle, a mobile phone and a single matchstick found in or around the Vauxhall Cavalier, which was abandoned partially burnt-out on a country road a few miles from the shootings.
He said that a DNA sample found on the buckle was 5.91 trillion times more likely to be Duffy's than someone else's, while a sample from inside the phone was 6.01 billion times more likely to belong to Shivers than another person.
The expert also said the DNA on the matchstick was 1.1 million times more likely to be Shivers than someone else.
But the academic's "True Allele" method of analysing mixed genetic samples and deriving a likelihood ratio is relatively new and has never been admitted as evidence in a UK or Irish court, and only on a few occasions in the United States.
Mr Mooney said: "The absence of a UK validation does not prevent the evidence of a US expert in DNA from being advanced before this court.
"The body of work that has been presented by Dr Perlin in support of his conclusion is a body of work which is recognised by the relevant scientific community."
He added: "We submit that the method used by Dr Perlin is based on the application of well-understood and long-standing principles. The only new area in this method, as he describes it, is the engineering of those principles into a working test system.
"It is truly a working test system."
He said it had been validated and approved in New York state and Pennsylvania and was used to identify victims who died in the 9/11 attack on the World Trade Centre in New York in 2001.
Defence counsel said Dr Perlin had a vested financial interest in gaining approval for his method, had failed to obtain widespread scientific acceptance and was overly secretive, but Mr Mooney said this was "misconceived and vexatious".
"When one looks at the vast body of works that have been presented by Dr Perlin, it is quite clear that he has opened his technology to the world for its review," he said.
"He has gone through a protracted period of evolving a stable, a secure and accurate system which is of benefit to the courts and because it is objective it takes no sides.
"It is available to the defence as much as to the prosecution. It can help absolve the innocent and convict the guilty."
He said it had been adopted in the US, where capital punishment exists.
"I respectfully suggest that Dr Perlin has demonstrated himself to be objective, impartial, authoritative, with eminent qualifications carrying out important work which, as he has indicated to the court, is properly validated in accordance with scientific principles and has been shown to work by comparative studies," he said.
"It therefore represents a body of science which is authoritative, which has been shown to be accurate and there is no evidence that can be produced to say that his figures are wrong."
Barry MacDonald QC, who represents Duffy, said the court would be "reckless" to allow the evidence to stand. He added the reception from other scientists had been "lukewarm if not positively hostile" with only five to 10 laboratories using it.
"How that can be seriously described by anyone as commanding widespread acceptance in any scientific community is quite frankly beyond me," he said.
The court will sit again on Thursday.