Warning: this article omits information that the Guardian and other news organisations are currently prohibited from publishing.

The court of appeal has refused to lift reporting restrictions following the secret trial of a London law student who was cleared of plotting a terrorist attack on the streets of the capital.

However, the lord chief justice, Lord Thomas, said that only the director of public prosecutions (DPP) could ask a court to sit in secret, and warned that MI5 and MI6 must not in future threaten to withhold evidence in a bid to secure courtroom secrecy.



Following an appeal brought by the Guardian and other UK media organisations, Thomas invited the parliamentary intelligence and security committee to investigate the role that MI5 and MI6 played in decisions that were taken around the prosecution of Erol Incedal.

“It is a significant, important and proper part of the duties of the security services of the United Kingdom that they act in accordance with the law,” Thomas said. “No part of the executive can refuse to provide the evidence required by the [DPP] on the basis that it perceives that it is not in the interests of national security to provide it.

“In a case involving national security ... it must be for the DPP, and the DPP alone ... to determine whether to prosecute and, if so, whether to apply to the court for part of the proceedings to be heard in camera [in secret].”

In a bid to deal with the accumulation of case law that remains secret, even to the courts, Thomas said also that he was establishing a working party that would examine ways in which closed judgments that were handed down in cases concerning national security could be available to courts dealing with similar cases in the future.

Incedal, 28, from south London, was arrested in October 2013 and found to be in possession of a bomb-making manual on a memory card hidden inside his mobile phone case.

Following representations from the intelligence agencies – of a nature that Thomas has described as “absolutely impermissible” – the Crown Prosecution Service decided that it wished to prosecute him in secret.

The media were told that although they would be permitted to report on the charges against Incedal and the eventual verdict, they would not be permitted to hear the evidence, nor be informed of his identity. He would be referred to only as AB.

After the media objected, the court of appeal ordered that Incedal could be identified and that the trial should be heard in three parts: there would be open court sessions, secret sessions, and intermediate sessions which the press could attend, but not report, pending a review by the trial judge, Mr Justice Nicol.

Throughout each of those intermediate sessions, the small number of journalists allowed into court nine at the Old Bailey were expected to surrender their mobile phones, which were locked in soundproof boxes.

At the end of each session, the journalists were obliged to hand their notebooks to police officers, to be locked in a safe at the back of the court. The officers watched closely to ensure the journalists did not attempt to remove any notes from the court.

During his trial at the Old Bailey, Incedal argued that he had a reasonable excuse for having the manual in his possession. The jury rejected this claim, however, and he was jailed for 42 months.

His friend Mounir Rarmoul-Bouhadjar, also 28 and from south London, pleaded guilty to possession of the same manual and was jailed for three years. Both men have since been released from prison.

However, the jury failed to reach a verdict on the more serious charge that Incedal faced: that of planning a terrorist attack. After a retrial, a second jury acquitted him.

At the end of the retrial, Nicol decided against lifting the reporting restrictions, with the result that the reasons why the jury reached its not guilty verdict could not be reported. Nor could the basis for Incedal’s claim that he had a reasonable excuse for possession of the manual be explained to the public.

Thomas said that the media’s second appeal raised important issues concerning public confidence in MI5 and MI6 and the accountability of the agencies. He said public accountability of the agencies could be achieved through an investigation by the ISC.

The lord chief justice added that nothwithstanding the importance of the open justice principle, Nicol had made the correct decision, in the interests of national security, and that the courts “should hesitate long and hard” before agreeing to a trial being heard in the same three-part manner.