An acclaimed television journalist who challenged a Bloody Sunday inquiry bid to get him to hand over material which could identify his sources was due to take the witness stand in Derry today.
Mr Peter Taylor, who has made a number of TV series and written several books on Northern Ireland's Troubles, is the latest journalist to face the tribunal having faced a bid to reveal source material.
In April 1999, the inquiry chaired by Lord Saville of Newdigate sought source material used in a BBC documentary made by Mr Taylor entitled Remember Bloody Sunday.
The programme was broadcast on January 28th, 1992, and carried interviews with soldiers who were on duty on the day when 13 people were killed on the streets of Derry.
Mr Taylor also interviewed civilian eyewitnesses.
The inquiry also sought material used in a book of Mr Taylor's acclaimed documentary series Provos- the first of a trilogy of programmes on the Troubles.
Mr Taylor has described Bloody Sunday as a defining moment in his career.
His visit to Derry on January 30th, 1972 - the day of the killings - was his first to Northern Ireland.
It was also his first assignment as a reporter for the ITN's This Weekprogramme.
He later claimed during the promotion of the series Provos: "I was ashamed at what had happened and ashamed at my own ignorance about Ireland.
"I was determined to try and understand how such a tragedy had occurred and why the conflict of which Bloody Sunday was a dreadful part, had arisen. The rest, as they say, is history."
Mr Taylor was due to appear at Derry’s Guildhall just 24 hours after another journalist was warned by the inquiry's chairman, Lord Saville, he could be forced to disclose his sources.
During hearings yesterday, former Sunday Timesreporter Mr Derek Humphry refused under cross-examination to reveal the identities of two republicans - the head of the Bogside IRA and a woman who was reported to be at a hastily arranged meeting of Provisionals when the shooting started.
Mr Humphry had worked on an unpublished investigative article with a colleague Mr Murray Sayle which claimed the Army had intended to trap IRA members taking part in the march, resulting in their arrest or them being shot.
However, the plan backfired because the republicans were unarmed.
Mr Humphry told the Saville Inquiry he had interviewed "15 to 20" Provisional and Official IRA contacts, some of whom he knew by name, while researching the article.
The interviews were conducted "on a no-names basis" at some IRA members' homes or in pubs.
Mr Humphry was warned at the end of his testimony by Lord Saville he could be forced to reveal his sources.
The chairman explained: "You will appreciate that we as a tribunal have a duty to try and seek the truth and indeed the whole truth about Bloody Sunday and it may therefore be necessary to ask you to come back at some stage and to see whether it is necessary for us to require you to answer the question as to the identity of those two people."
The inquiry has clashed with other journalists over the revealing of sources.
Channel Four news presenter Mr Alex Thomson and his former producer Ms Lena Ferguson were warned they could be in contempt of court if they refused to disclose the identities of soldiers they interviewed.
PA