A senior garda has been appointed to examine reasons behind the collapse of a trial into the killing of Northern Ireland prison officer David Black.
Mr Black (52) was on his way to work at the high-security Maghaberry Prison in Co Antrim in November 2012 when he became the victim of a drive-by shooting.
A dissident republican organisation calling itself the IRA said it carried out the murder.
Damien McLaughlin (41) was accused of aiding and abetting murder, possession of articles for use in terrorism, preparation of terrorist acts and belonging to a proscribed organisation.
Prosecutors decided not to appeal against a judge’s ruling that part of the evidence was unsafe.
Mr McLaughlin, from Kilmascally Road, Dungannon, Co Tyrone, appeared at Belfast Crown Court at the Laganside complex on Thursday.
The prosecution case against him rested on the evidence of Stephen Brady, who was interviewed by the Garda.
Mr Brady allegedly identified Mr McLaughlin as the man who moved a Toyota Camry car, later allegedly used by the gunmen to carry out the ambush of Mr Black.
Mr Justice Adrian Colton told the court: "I direct that a not guilty verdict be entered in respect of this accused."
Mr Black was a father-of-two from Cookstown, Co Tyrone. His family was in court.
Afterwards Mr Black’s son Kyle said: “To hear today that the trial had collapsed was just devastating. The wound over time scabs over a bit but in the last few weeks, especially today, that scab has been pulled off and it is incredibly raw.”
He said the lives of the Black family members had been changed forever by the killing and it was difficult to understand why someone would decide to take a caring and compassionate man from his family.
The chances of justice were getting slimmer by the day but he still hoped someone would be held accountable, he said.
Separately, Assistant Garda Commissioner John O’Driscoll has been appointed “ to conduct a fact finding exercise into the circumstances, from a Garda perspective, that led to the dismissal of this case”.
Mr O’Driscoll said that since the interviews were carried out by Garda members in Mr Black’s case, interview procedures had improvement and training had changed.
“We have an inspector who is now national interview adviser and he has that role of examining the quality of interviewing and trying to make sure there is a consistency throughout the organisation,” he said.
“But we will look at this case, examine the comments of the judge and see what can be done to ensure this circumstance doesn’t arise in the future.”
Earlier this week, the Judge said: “The risk of unreliability of Brady’s statements is such that they should not be admitted by way of hearsay.”
He said the profanities used by the interviewers were “excessive and oppressive”.
The judge said the interviews were conducted in such a way as to “undermine” the suspect’s right to silence.
“In the course of the interviews the suspect was the subject of threats and inducements.I am not satisfied that it is in the interests of justice for the hearsay evidence to be admitted.
“To the contrary, because of the particular circumstances in which the evidence was obtained, I consider that it is necessary in the interests of justice that it should not be admitted and that a trial depending upon it should not be allowed to proceed because any conviction based on that evidence would be unsafe.”
