The Northern editor of the Sunday Tribune, Mr Ed Moloney, has failed in his attempt to overturn a court order instructing him to hand over notes of conversations he had with the man now charged with the murder of Belfast solicitor Mr Pat Finucane.
Mr Moloney has been given seven days to comply with the order or face an unlimited fine and/or up to five years' imprisonment.
At a sitting of Antrim Court yesterday, Judge Anthony Hart said he was satisfied that the notes may help inquiries into the killing and adjourned the hearing to allow Mr Moloney's defence team study a 20-page outline of his decision.
Mr Michael Lavery QC, representing Mr Moloney, later told the court that his client would appeal the decision with the County Court, or through a direct appeal to the High Court in Belfast or would apply for a judicial review of the case.
Detectives involved in the reopened investigation of the 1989 killing of Mr Finucane requested the order under provisions in the Prevention of Terrorism Act as a result of an article written by Mr Moloney after the arrest of Mr William Stobie in June.
Mr Stobie, a former UDA quartermaster, claimed in interviews with Mr Moloney in 1990 that he was an RUC informer at the time of the killing and that he had told his police handler that an attack was imminent although he did not know who was to be targeted.
"I will not, I cannot, give my notes to the Stevens team without helping to compromise the profession of journalism in these islands and my own career as a reporter for the Sunday Tribune," Mr Moloney said yesterday.
"This has been a highly questionable action by the Stevens team. So far detectives brought in to investigate allegations of collusion in the killing of Pat Finucane have pursued only those who have widened and publicised further allegations of collusion. "I must ask the question - why are the Stevens team behaving like this? Are they trying to punish me for trying to publicise these allegations?"
The editor of the Sunday Tribune, Mr Matt Cooper, said the newspaper was "deeply disappointed" by the decision and intended to challenge it using whatever route was deemed appropriate.
Judge Hart said the case was unlike previous cases where a journalist sought to protect sources because Mr Moloney had reached an agreement with Mr Stobie that the interviews would act as a form of "insurance" for the loyalist if he was blamed for the killing.
Mr Seamus Dooley, of the National Union of Journalists, said the Stevens inquiry was involved in a "fishing exercise".
Amnesty International has said any prosecution of Mr Moloney would have an "intimidatory" effect on investigative journalism, while Human Rights Watch said the decision set a "dangerous precedent".