What is likely to be the final battle in a six-year campaign to force the BBC to release a report into its Middle East coverage began at the Supreme Court on Wednesday.
London solicitor Steven Sugar first sought the publication of the Balen Report early in 2005 under the newly introduced Freedom of Information Act.
But although he died early this year, his widow, Fiona Paveley, was granted permission to continue the fight in his name.
A number of hearings have already taken place in the Information Tribunal, the High Court, the Court of Appeal and the House of Lords.
This week's case was due to have come before the Supreme Court in February but was postponed because of Mr Sugar's death the previous month.
The report was presented to the BBC in November 2004 by senior editorial adviser Malcolm Balen, a former Nine O'Clock News editor, who examined complaints into the organisation's coverage of the Arab-Israeli conflict. It led to the creation the following year of the post of Middle East editor, which was filled by Jeremy Bowen.
The corporation has so far resisted the demand for publication, by arguing that documents for the purpose of journalism are exempt from disclosure under FOI legislation.