They therefore held that “the core of the trial must be heard in camera” but that the following could take place in open court: swearing in of the jury, reading the charges to the jury, at least part of the judge’s introductory remarks to the jury, at least part of the prosecution opening, the verdicts and (subject to further argument) sentencing if any convictions resulted. “It is important to underline that a defendant’s rights are unchanged whether a criminal trial is heard in open court or in cameraand whether or not the proceedings may be reported by the media.”

A small group of “accredited journalists” may attend, drawn from the media parties to the proceedings. Notes can be made but must be stored securely until the end of the trial, a transcript of the proceedings (excluding the discrete ex parte areas) will be available for review at the conclusion of the proceedings in connection with any further consideration of publication and a “tailor made” order should be made.

Allowing the media’s appeal against the anonymisation of the defendants, Gross LJ said: “We express grave concern as to the cumulative effects of holding a criminal trial in camera and anonymising the defendants. We find it difficult to conceive of a situation where both departures from open justice will be justified.”

Isabella Sankey, Director of Policy for human rights organisation Liberty, said: “The judges are clear that open justice is a priceless foundation of our system and faced with a blacked-out trial we now have a few vital chinks of light.“But their wholesale deference to vague and secret ministerial ‘national security’ claims is worrying. Shutting the door on the core of a criminal trial is a dangerous departure from our democratic tradition.”

The trial of Erol Incedal and Mounir Rarmoul-Bouhadjar, who are charged with terrorist offences, was due to start on 16 June at the Central Criminal Court at the Old Bailey.