Police yesterday confirmed that it is actively investigating how recordings of interviews with Kevin McDaid’s son, Ryan, have been posted online.
Official recordings of detectives interviewing Ryan surfaced on the internet in May.
They have been uploaded to a storage site where they can be listened to members of the public.
Now a senior police officer has been appointed to investigate whether the leak came within Coleraine police station or from some other source.
Last week nine men received between six months and eight-and-a-half years prison terms on charges ranging from grievous bodily harm, assault, affray and intimidation in connection with the killing of the Kevin McDaid.
The 49-year-old Catholic father of four, died after he was attacked outside his home in May 2009 in what a judge described as an ugly sectarian incident.
Murder charges against some of the defendants were withdrawn in May when it emerged that Mr McDaid had an underlying heart condition which could have killed him at any time.
The recordings surfaced days after the murder charges were withdrawn and police will look at whether they were posted deliberately.
They reveal how Ryan had lifted a knife to defend his father and accidentally nicked his hand.
When news of the leaked recordings circulated on internet forums the McDaid family were subjected to sectarian abuse.
After a police interview an individual is given a tape to keep while the defence team receives transcripts.
The probe will investigate who has copies or access to the tapes.
A police spokesperson said: “Police have begun an investigation.
“Anyone with information about the appearance of this material on social media is asked to contact Serious Crime Branch Detectives at Maydown on the non emergency number 101.
The McDaid family have not commented on the matter.