An internal inquiry will now be conducted to determine what went wrong, with five future cases under review.
Head of Law Enforcement Patrick Rice said: ‘The investigation into this case has not met the high standards the community rightly expects from us and we apologise unreservedly.’
An 18-year-old man, who was 17 at the time of his first court appearance and cannot be named for legal reasons, was acquitted of rape after Crown advocate Gary Perry offered no evidence against him.
Judge Russell Finch ordered the nine jurats to deliver a verdict of not guilty.
