A loyalist activist who claims police unlawfully seized his journalistic material linked to the Kingsmill massacre has now received a request for the files from the coroner investigating the killings.
The Coroners' Service has written to Jamie Bryson days before he is due in Belfast High Court for a case challenging whether officers who were investigating an alleged door staff licensing breach had the right to take unrelated documents he contends are covered by journalistic privilege.
Mr Bryson, a blogger and commentator who edits a website called Unionist Voice, is a temporary freelance member of the National Union of Journalists (NUJ). He has used the website to publish articles about the Kingsmill murders.
The coroner's request for sight of Mr Bryson's source material - documents he says were taken by police - comes amid an ongoing inquest into the notorious sectarian outrage that saw 10 Protestant workmen lined up and shot dead by republican paramilitaries in January 1976.
In the judicial review hearing on Wednesday, Mr Bryson will seek to challenge the legality of the warrant used by the Police Service of Northern Ireland (PSNI) to seize the material. The PSNI was executing the warrant on behalf of the Security Industry Authority (SIA) - the statutory organisation responsible for regulating the private security industry in the UK.
Mr Bryson was arrested during August's raid and later released without charge. The investigation into an alleged offence of unlawfully supplying door staff continues. He denies any wrongdoing.
With controversy around the 29-year-old's membership of the NUJ - the local branch in Belfast opposed the union's decision to admit him - the High Court case is also likely to focus on what defines a journalist and whether he is entitled to invoke journalistic privilege in the eyes of the law.
"It is somewhat of a major development that the Coroners' Court has now entered into the issue to request copies of the journalistic material regarding Kingsmill that I say was unlawfully seized by the PSNI," said Mr Bryson.
"It adds an extra layer of pressure to the PSNI in relation to justifying this seizure."
Mr Bryson said he would always do anything possible to assist the Kingsmill families, but he expressed concern at the request for his papers.
"If I were to provide this documentation to the coroner then it would no longer be material held for the purposes of journalism and PSNI could then retain material which they should never have in the first place as I would have waived journalistic privilege by providing material held in confidence to a third party," he said.
Mr Bryson's lawyers will argue that the warrant to seize material should have been granted by a county court judge, rather than a lay magistrate - as they will claim police should have known journalistic material would have been on site.
The loyalist campaigner says material taken by police also includes papers on the sale by Ireland National Assets Management Agency (Nama) of its Northern Ireland portfolio; the 1989 IRA murders of senior RUC officers Chief Superintendent Harry Breen and Superintendent Bob Buchanan; the 'On the Runs' controversy; and allegations around the exploitation of the Roma community in south Belfast.
"They have gone in through the back door essentially to seize a wide range of journalistic material which they didn't have the power to seize in relation to this investigation and is far beyond the scope of the warrant and is essentially irrelevant to what they claim to be investigating," he said.
"I can't for the life of me understand what files from 1976 or files relating to Nama or the Kingsmill massacre or the murder of RUC officers has got to do with investigating door supervisors - it is quite simply beyond me. It was a fishing expedition."
Mr Bryson insists he is entitled to the same protections as any journalist working for the mainstream media.
"I didn't define what is a journalist, I didn't write the law, I didn't write the NUJ's definition," he said.
"But in relation to those definitions I am held in equivalence in terms of journalistic material with professional journalists who work for mainstream outlets, that's not my fault."
He said his case could have "ramifications" for the wider journalistic profession.
"If the PSNI get a judgment in their favour whereby they can contrive some type of investigation to get through the door, but while they are still there they can scoop up a whole load of journalistic material, if there is contentious issues with journalists they can simply come in under the auspices of something else and take all their computers and all their notes without the judicial oversight of having to go to a county court judge," he said.
The case is the second before the Northern Ireland courts challenging the right of police to seize journalistic material that is unconnected to the investigation they are conducting.
Police who raided the offices of two Belfast filmmakers last year with a warrant to remove material related to their documentary on a loyalist massacre also took away a tranche of papers linked to a journalistic probe into an alleged paedophile priest.
The search came as producers Trevor Birney and Barry McCaffrey were arrested over the alleged theft of a police watchdog document that appeared in their film No Stone Unturned on the murders of six men in Loughinisland, Co Down, in 1994.
The men have accused police of massively overstepping the terms of their warrant and seizing years of work they maintain should be protected by journalistic privilege.
A judicial review taken by Fine Point Films is due to be heard later this year.
In relation to Mr Bryson's claims, the PSNI said it would not comment on named individuals. The SIA has been contacted for comment.