Police are to initiate inquiries into a key prosecution witness following the collapse of the trial of an elderly couple accused of killing their disabled granddaughter.
Director of Public Prosecutions Barra McGrory QC has asked Chief Constable Matt Baggott to consider whether a criminal offence may have been committed.
David and Sarah Johnston, aged 89 and 85 respectively, were acquitted of Rebecca McKeown's manslaughter after the trial was halted in May. The severely disabled teenager died from pneumonia and the prosecution claimed that the 14-year-old developed the illness after she was injured during a sexual assault while in her grandparents' care.
A Public Prosecution Service (PPS) spokesperson said: "Following a careful examination of the issues arising from the evidence of a key prosecution witness at the trial of R-v- David and Sarah Johnston, the director of Public Prosecutions for Northern Ireland, Barra McGrory QC ... has requested the chief constable to ascertain and provide information to him on the grounds that a criminal offence may have been committed."
In May the PPS said the decision to discontinue the prosecution was taken "as a result of the evidence given by a witness and medical experts at trial".
Referring to the testimony of Dr Mary Donnelly, the locum GP who examined the teenager five days before her death, the PPS said that on the morning she was due to give evidence the doctor "provided an additional account of her examination of Rebecca".
It said: "This account had not previously been given by the witness to either the police or prosecution over the preceding 11 years."
Rebecca died in hospital in March 2001. Mr and Mrs Johnston, from Carwood Drive, Glengormley, Co Antrim, denied manslaughter and child cruelty charges against Rebecca. The judge directed the jury to acquit the couple after the prosecution collapsed in the face of evidence that cast doubt on the cause of death and revealed a new possible cause of injury to Rebecca.
During the trial the prosecution claimed that Rebecca's pneumonia was a direct result of blood loss and shock that she suffered following an alleged sexual assault at the hands of one or other of her grandparents. But the PPS decided to offer no further evidence following the testimony of Dr Donnelly and that of the state pathologist for Northern Ireland, Professor Jack Crane.
Dr Donnelly admitted for the first time, 11 years after examining the profoundly disabled child, that two of her fingers "unintentionally" slipped inside her. Professor Crane said that he could not be sure that the laceration had led to the pneumonia which killed Rebecca.