Is the justice and security bill a threat to fundamental legal liberties or a necessary veil to protect state secrets? Here's what you need to know about the expansion of trials behind closed courtroom doors

1. The issue at a glance

2. The legal origins

3. Why are secret trials in the news?

4. A short history of secret hearings

5. What's next?

6. The main arguments against the bill

7. The main arguments for the bill

8. What will disappear behind closed courtroom doors?

9. Key players

10. Glossary

11. FAQ

12. The final word

1. The issue at a glance

The justice and security bill's most controversial element is the extension of secret courts, known as closed material procedures (CMPs), into the civil courts in England and Wales. Opponents believe the powers will enable ministers, rather than judges, to manipulate the way evidence is withheld or presented in the courts – depriving claimants of a fair trial. The government claims the reform will enable judges to hear a greater range of national security cases. The bill also alters parliamentary scrutiny of the intelligence services.

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2. The legal origins

In May 2010, the government was forced to pay out millions of pounds in compensation to Binyam Mohamed and other former Guantánamo Bay detainees.

Binyam Mohamed, the UK resident secretly rendered to Guantánamo Bay, whose case sparked the row over intelligence disclosed in court. Photograph: Shaun Curry/AFP

The settlement came after the court of appeal rejected requests by MI5 and MI6 that they be able to present security evidence in secret without disclosing it in full to the claimants. "Trials should be conducted in public and the judgments should be given in public," the judges ruled. Rather than reveal "sensitive" intelligence, the government settled out of court claims for wrongful imprisonment and complicity in torture.

The result, according to the former justice secretary Ken Clarke, has been a "UK justice system unable to pass judgment on these vital matters". Claimants, he argues, are denied any judicial findings while the intelligence agencies cannot clear their names. The government says the justice and security bill is designed to ensure such a predicament never recurs by extending the use of secret courts while preserving intelligence-sharing with the US and other allies.

Without transparent justice, critics counter, abuses of power will remain hidden.

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3. Why are secret trials in the news?

The legislation, introduced in the House of Lords, has provoked deep anxiety among civil liberties groups, senior lawyers and politicians who fear it is the thin end of a wedge, overturning long-established, common law precedents about fair and open justice. The Labour party supports some elements but argues that the secret court developments are "too widely drawn" and create "damaging mistrust and a dangerous gulf between government and the citizens it is purporting to protect".

The bill is also sharpening divisions between Liberal Democrats and Conservatives within the coalition. The prime minister, David Cameron, justified secret hearings on the grounds that "... it isn't currently possible to use intelligence information in a court of law without sometimes endangering national security".

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4. A short history of secret hearings

Closed, or "in camera", hearings are not unprecedented. Cases in the family division of the high court relating to child custody and divorce issues are regularly held in private.

Public interest immunity (PII) certificates date back to the mid-20th century and empower courts to make an order, usually at the request of the government, preventing disclosure of secrets if their release is deemed damaging to the public interest. Neither side in such cases can rely on the withheld information.

So-called "closed material procedures" (CMPs) go one stage further, enabling authorities to introduce sensitive information in a trial that can only be seen by the judge and security-cleared "special advocates" who represent the interest of an individual claimant. The special advocate may not give his or her client precise details of the evidence and can only provide a "gist" or loose summary. The claimant may not therefore be aware of all the allegations being made. Critics say this results in parties to a legal dispute no longer being on an equal footing, tilting the advantage in the government's favour.

The Royal British Legion and Nick Clegg pressured the government to exempt coroners' courts from the bill. Photograph: Jeff J Mitchell/Getty Images

CMPs are used in employment tribunals, special immigration appeals commission (SIAC) hearings and the investigatory powers tribunal (IPT), which handles complaints about the intelligence services. The justice and security bill would extend closed material procedures into the main civil courts, allowing the government to exploit intelligence material to defend itself against allegations such as torture.

In April 2012, parliament's influential human rights committee, which draws members from both the Lords and Commons, condemned the government's justice and security green paper proposals for failing to make the case for extending CMPs into civil proceedings or inquests. "The rule of law requires that decisions about the disclosure of material in legal proceedings be taken by judges not ministers," it declared, "and the current legal framework of PII has not been shown to be inadequate."

Under pressure from the Royal British Legion and Nick Clegg, the Liberal Democrat leader, the government agreed in May to exempt coroners' courts from the newly introduced bill.

The prospect of grieving parents of servicemen killed in Afghanistan being barred from security-sensitive sessions of an inquest into the death of their son or daughter and never discovering why they had died was judged to be politically indefensible.

In September, the Liberal Democrat party conference voted overwhelmingly to reject the bill.

The government's own watchdog, the Equalities and Human Rights Commission, warned in October that the bill could be incompatible with the Human Rights Act.

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5. What's next?

Peers opposed to the bill failed to remove secret court proposals entirely in the Lords but imposed a series of safeguards giving judges, rather than ministers, greater powers to decide when to hold a CMP. These amendments were altered again in the Commons. The legislation also contains clauses on changing the mechanism of parliamentary oversight of the intelligence services and is likely to provoke intense debate in the Commons.

Jack Straw, who faces legal action over claims that he personally permitted the illegal rendition of a Libyan dissident in 2004. Photograph: Andy Rain/EPA

In the meantime, a practical test of how courts handle security sensitive information came before a high court judge, Mr Justice Mitting. A case has been brought against the Foreign Office by Noor Khan, whose father, Malik Daud Khan, was killed in a CIA air strike in Pakistan by a drone in 2011. The UK is alleged to have been involved because it shared intelligence with US agencies. The preliminary hearing dealt with the question of whether the case can be heard without resorting to a closed material procedure.

Lawyers acting on behalf of two Libyan families who are bringing proceedings against the British government as well as Jack Straw and former MI6 counter-terrorism official Sir Mark Allen, following their rendition to Tripoli, are also moving quickly in the belief that the families will be denied justice once the bill becomes law.

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6. The main arguments against the bill

• Secret justice cannot constitute a fair trial and could damage public confidence

• The existing system is not broken

• Judges, not politicians, should decide

• Evidence of torture will be suppressed by the new generation of secret courts

Secret justice cannot constitute a fair trial and could damage public confidence

Critics point to a key passage in the supreme court's decision in 2011 on Al Rawi v the security service (pdf), in which Lord Kerr asserted: "Evidence which has been insulated from challenge may positively mislead … the right to know the case that one's opponent makes and to have the opportunity to challenge it occupies … a central place in the concept of a fair trial." Also, the bill is silent on the open justice principle. The joint committee on human rights described this silence as "a serious omission". The government's own impact assessment conceded that the proposed new law could undermine public confidence in the court system (pdf). There are concerns that the bill may have an adverse impact on the Northern Ireland peace process.

The existing system is not broken

Most damaging for the government's case is the opposition of special advocates who already operate CMPs in SIAC and other specialist courts. In their submission to the government's green paper proposals (pdf), they declared: "There is no fundamental difficulty with the existing principles of public interest immunity (PII), which have been developed by the courts over more than half a century and which enable the courts to strike an appropriate balance between the need to protect national security (and other important public interests) and the need to ensure fairness."

Judges, not politicians, should decide

In the face of criticism, the government agreed that a minister alone should not be able to order a CMP. That reassured few experts. David Anderson QC, the independent reviewer of terrorism legislation (pdf), pointed out residual problems when questioned in parliament in June. "Under the procedure devised in the bill, the judge does have the last word," he said. "The only difficulty is that that word is dictated to the judge by the secretary of state. First, the judge can make a decision only if the secretary of state makes an application and has no other jurisdiction to consider it. Secondly, when the judge does come to consider it, it is not for him to weigh up the relative merits of PII or CMP, or to decide what the fairest way would be to decide the case. The judge's hands are effectively tied."

The United Nations' special rapporteur on torture has intervened in the UK secret courts debate. Photograph: Joshua Lott/Reuters

Evidence of torture will be suppressed by the new generation of secret courts

The United Nations' special rapporteur on torture, Professor Juan Méndez, an Argentinian, has intervened in the UK debate, warning that wrongdoing by security and intelligence agencies if undisclosed will not be confronted. "If a country is in possession of information about human rights abuses, but isn't in a position to mention them, it hampers the ability to deal effectively with torture," he told an audience at Chatham House in London in September 2012. The fact that the government has applied for the use of closed material procedure in a court case in which it is a defendant could itself be kept secret.

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7. The main arguments for the bill

• Cases that cannot now be tried will receive justice

• Not perfect but better than nothing

• Intelligence services will become more accountable

• Security co-operation with our closest allies is at risk without legal reform

Cases that cannot now be tried will receive justice

Ken Clarke spelled out in the foreword to the green paper (pdf) his rationale for expanding the use of CMPs. "... the UK justice system [is now] unable to pass judgment on these vital matters: cases either collapse, or are settled without a judge reaching any conclusion on the facts before them.

Former justice secretary Ken Clarke spelled out his rationale for expanding the use of CMPs. Photograph: Dave Thompson/PA

"It leaves the public with questions unanswered about serious allegations, it leaves the security and intelligence agencies unable to clear their name, and it leaves the claimant without a clear legal judgment on their case.

"... The prize is improved executive accountability, a court system equipped to handle sensitive material, and security and intelligence agencies that are able to get on with their job: a safer Britain, a fairer Britain."

Not perfect but better than nothing

The former independent reviewer of terrorism legislation, the Liberal Democrat Lord Carlile, describes the debate as involving "finely balanced issues". He comes down on the side of extending closed material procedures. "The puritans in this debate demand that 'open justice' must be protected, whatever the cost to the public and to the intelligence needs of our country," he wrote this summer. "Subject to some fine tuning, the government is on the right track with a responsible piece of legislation … It should not be forgotten that claimants themselves have consented to closed hearings, realising that they were the only way in which their concerns would be properly scrutinised – one reason why I believe the government should ensure that both parties in a case can apply for a CMP."

The current independent reviewer, David Anderson QC, believes the proposals would be "tolerable" as a last resort. He said there is "a small but indeterminate category of national security-related claims, both for judicial review of executive decisions and for civil damages, in respect of which it is preferable that the option of a CMP – for all its inadequacies – should exist."

Intelligence services will become more accountable

The security services, who have lobbied for and publicly supported the bill, insist that nothing currently revealed will be hidden in future. In a speech at the Mansion House this summer, the director general of MI5, Jonathan Evans, declared: "At present our ability to account for our actions in the courts is constrained by the fact that sensitive national security related material relevant to civil proceedings can only be considered in open court. This means that such material cannot in practice go into court at all. This situation is bad for us, bad for the other party to proceedings and bad for the administration of justice.

"... No material that is currently considered in public will be made secret under the new arrangements and the effect will be that more, rather than less, material will go before the courts. But the sensitive material will be protected. This will mean better justice and better accountability."

Security co-operation with our closest allies is at risk without legal reform

Malcolm Rifkind, the former defence and foreign secretary, believes that "foreign intelligence material provided by another country on the strict promise of confidentiality" should remain behind closed doors. "Many of the most serious terrorist plots in the UK in the past decade have had significant links abroad, so foreign material is often vital for the protection of the UK. When other countries share material with us, they want to know that we will protect it. It still belongs to them and is controlled by them: it is not ours to do with as we wish. This 'control principle' is sacrosanct and we must not break it. If we do, foreign agencies will not trust us and will not share material with us in future."

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8. What will disappear behind closed courtroom doors?

Critics of the bill fear that a host of security scandals unearthed with the help of court challenges, including allegations of torture and secret rendition, would never have been exposed under the bill's proposed system of closed material procedures. Even fundamental personal rights such as freedom from imprisonment, guaranteed by the ancient writ of habeas corpus, might be compromised by the new regime, peers have suggested. The fact that a court could sit in secret without giving notice to the public or the media of a forthcoming hearing has drawn comparisons with the excesses of privacy superinjunctions. The government dismisses such claims as alarmist.

While the government claims that the proposals are intended to protect the control principle that covers intelligence provided by foreign governments, the material sought in the Guantánamo case were mostly internal British government communications, and their disclosure caused grave embarrassment. The government says claimants will receive a summary of the closed material sufficient for them to instruct the special advocate representing their interests.

The US government made its first complaint that disclosure in the Binyam Mohamed case would damage the UK-US intelligence sharing relationship only after the foreign office asked it to do so.

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9. Key players

• Ken Clarke, now a cabinet minister without portfolio but with a place on the National Security Council, will continue to steer the legislation through parliament even though no longer justice secretary. The Cabinet Office is now in charge of the bill.

Some key figures in the secret courts debate: (clockwise from top left) Lord Lester, Shami Chakrabarti, Jonathan Evans and Sadiq Khan. Photograph: Rex Features/PA/Sarah Lee for the Guardian

• Jonathan Evans, director general of MI5 – said by opponents to be the moving force behind the secret courts bill.

• David Anderson QC, the independent reviewer of terrorism legislation, occupies a pivotal position in the debate with government, intelligence agencies and civil liberty groups all trying to recruit him to their cause.

• Lord Lester, the veteran Liberal Democrat peer and civil liberties campaigner, has been active in the Lords attempting to insert safeguards "for the principle of open justice" into the bill.

• Sadiq Khan, Labour's justice spokesman, is influential in deciding where his party strikes the balance between civil liberties and national security. It is an issue on which, he admits, the party "still bears the scars" following Iraq, Afghanistan and the war on terror.

• Shami Chakrabarti, director of the human rights group Liberty, is a determined opponent of the bill. She warns that the security services will be able to defend allegations of misbehaviour behind closed doors by hiding behind the mantra of "national security". Other groups such as Reprieve and Justice are active campaigners against the proposals.

• Dinah Rose QC, a leading barrister who has appeared as a special advocate, is a prominent critic of the bill. Her Atkin Memorial lecture, Beef and Liberty: Fundamental Rights and Common Law (pdf), is an impassioned rejection of the proposals.

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10. Glossary

Closed material procedures (CMPs): secret court hearings where only the judge and security-cleared special advocates are given access to sensitive intelligence material.

Special advocates: the security-vetted lawyers who are permitted to participate in CMPs, representing claimants or the government.

Gisting: special advocates are permitted to disclose to clients a simplified summary or "gist" of intelligence material used in secret hearings while withholding specific details.

Norwich Pharmacal court orders: developed to identify alleged infringers of intellectual property rights such as patents, one was deployed in the Binyam Mohamed case to try and force the UK government to hand over sensitive security material obtained from the US.

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11. FAQ

Is this the end of fair trials?

Critics claim that under a CMP, the legal playing fields are no longer even, entrenching the government's advantage in any secret court case. The government insists such measures will only be used in a very limited number of cases and that courts, including Strasbourg, have found that CMPs are capable of delivering fair trials.

Have UK courts ever exposed US military secrets?

No examples have ever been given of past "betrayals" of confidential intelligence material obtained from allies. However, the government argues that the overturning of the Foreign Secretary's PII certificate in Binyam Mohamed - and publication of seven paragraphs of advice - caused damage to the US-UK intelligence-sharing relationship and national security.

How large is the problem?

The number of civil cases affected is likely to be small but it is the expansion of the principle of closed material procedures that worries civil liberties groups. In the justice and security green paper, the Treasury solicitor's department claimed that "sensitive information was central" to 27 cases then before the courts.

A great many cases against the British government that arise from the Troubles in Northern Ireland are, however, now being prepared by lawyers in the province, and the disclosure that British special forces were involved in the mass detention of Iraqi civilians, possibly unlawfully, following the 2003 invasion, means that the government cannot be sure how many arguable claims it could face in the future as a result of that conflict.

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12. The final word

• "No country allows [spies] to give evidence in court. You'd have terrorists in the public gallery lining up making notes" – Ken Clarke, when justice secretary.

• "This toolkit for cover-ups would mark the end of a fair trial tradition admired worldwide for centuries" – Shami Chakrabari, Liberty.

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Further reading

Justice and security green paper (pdf)

Responses to consultation on justice and security green paper

Justice and security bill

Parliament's joint committee on human rights' report on the justice and security green paper

Commons Library standard note on closed material procedures and special advocates

Justice and security House of Lords library note

Reprieve's take on the justice and security bill

Justice's take on the justice and security bill

Liberty's take on the justice and security bill (pdf)

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