The key points, set out late last year in a Green Paper on Justice and Security, include a sweeping power to allow Ministers to withhold evidence they deem ‘sensitive’ from any civil open court hearing or inquest, if the Minister thinks disclosure would cause ‘damage to the public interest’

The Green Paper also states that in cases where this ‘closed material procedure’ was invoked, the only person apart from the judge and the lawyers representing the Government who would be allowed to see the secret evidence would be a ‘Special Advocate’.

After the 2010 Election, say the sources, MI5’s Director-General, Jonathan Evans, began a Whitehall lobbying campaign, arguing that the scrutiny Mr Mohamed’s case had directed at his agency had caused severe damage. He was also trying to overturn a decision by the Supreme Court, made after former Guantanamo prisoners sued the Government for damages.
Although the Government had already settled the case by paying them millions, MI5’s lawyers tried to get the court to agree that even without legislation, they should have the right in future to have evidence heard in secret, concealed from all but Special Advocates.
The Supreme Court’s response was withering. In the words of one of its judges, Lord Kerr: ‘The right to be informed of the case made against you is not merely a feature of the adversarial system of trial, it is an elementary and essential prerequisite of fairness.’