Tassagh fire deaths: forensics expert addresses trial
The principal scientific officer of the NI Forensic Service has been giving evidence to the trial of four brothers accused of a double murder.
Martin, Niall, Christopher and Stephen Smith are all accused of the murders of Thomas O'Hare and Lisa McClatchey.
Their remote cottage near Tassagh in County Armagh was attacked and burned by a gang of masked men in 2006.
Walter McCorkill told the jury in Armagh that he had identified and examined three separate scenes.
One was the scene of the blaze. He also examined a nearby laneway that had been identified as a "possible getaway or pick-up point", and a burned-out vehicle at a local quarry.
Dealing first with the house at Foley Road, he said three-quarters of the roof was missing and that the living room, kitchen and hallway had all been "completely destroyed". All the other rooms had also been damaged to some extent.
Asking Mr McCorkill about the explosion that had occurred, a prosecuting barrister suggested that at one point it had "literally raised the roof" of the bungalow and the scientist agreed this was the case; the roof of the house had been briefly lifted off by the sheer force of the blast.
The jurors were taken through dozens of photographs of the scene demonstrating how, in the scientist's opinion, pools of "accelerant" had been spread around the house before it was set alight.
He described the resultant blast as a "low order dispersal vapour explosion" consistent with petrol vapour having been ignited.
He also described how there was a strong odour of petrol throughout the house. Three large containers had also been found.
The remains of a sledgehammer were found during the excavation of the living room.
Several items of partially burned clothes were found away from the house on two different routes; one leading across a field at the back of the house and the other around the back of a new-build site nearby, where Mr McCorkill found partially burned clothing, a mobile phone and a bank card in the name of Stephen Smith.
He told the jury that he had attended the post-mortem examinations of both Mr O'Hare and Ms McClatchey, and that Ms McClatchey's injuries had been more extensive than those suffered by Mr O'Hare.
An examination of clothing removed from Mr O'Hare revealed the presence of petrol vapour.
Mr McCorkill said the garments had been in contact with liquid petrol.
Asked if it was possible the wearers had been simply standing in a room with petrol vapour in it, Mr McCorkill said it was his opinion there had been "direct contact" between the clothing and liquid petrol.
He could not, however, say if petrol had been poured over Mr O'Hare or if he had, perhaps, fallen into a pool of petrol.
Tests of Ms McClatchey's clothing showed a similar result. Some of her clothing also tested positive for the presence of paraffin.
The trial continues.