• Vote on Bill took place at same time as gay marriage vote
• Bill could give power to cover-up details on events such as Hillsborough
• Legal system would be weighted in favour of the powerful

While all attention at Westminster was focused on whether to allow gay marriage, this Coalition Government did something furtive – something that is not only much less liberal, but coldly terrifying.

Dictatorial ‘Secret Justice Bill’ was snuck in through the backdoor.

Under the cover of the furore, it quietly disinterred the corpse of its ‘Secret Justice’ Bill. This Bill creates extraordinary new legal powers to keep official dealings hidden from us. It changes all the comforting certainties about the rule of law in Britain.

Most of us have some kind of grasp of what is officially called the Justice and Security Bill.

But it can be hard to imagine what it would actually mean  in practice.

The Government wants us to think its scope is limited to rare and arcane disputes, perhaps born of foreign battlefields. Or ones that sound as if they belong in spy novels, involving CIA ‘black ops’ and ‘dark jails’. But if it becomes law, the effects will be felt much closer to home.

The shocking outcome of the recent Hillsborough Inquiry, bringing justice at last to 97 families? If similar circumstances were to arise again, it is likely that justice would never be delivered: if the families tried to sue, alleging a bungled police operation and a subsequent cover-up, the Bill would give the authorities the ability to keep the truth concealed.

A case brought against the Ministry of Defence by families of soldiers killed in a foreign deployment, alleging their loved ones’ equipment was defective? This is not mere hypothesis. Many argue now that the British death toll in Afghanistan has been higher than it should have been because some of our military vehicles were too vulnerable to roadside bombs.

With this law enshrined, the Government could insist on a closed, secret hearing. There, it could present evidence denying such claims. No one could challenge it, because no one directly affected by the case would ever know what it was.

Or take the very real, current scandal of the women green activists who unknowingly entered sexual relationships with undercover police officers.

 Those defending such a case could be entitled to a secret hearing, at which they could claim that such tactics were entirely justified, on the basis that the women posed some kind of threat to national security.

This is the reality of a society regulated by secret justice:  a legal system weighted irredeemably in favour of those in power. The legislation had previously been watered down considerably, and wisely, by the House of Lords. Now, it is not just as bad as it was when introduced last year. It’s even worse.

Under the resuscitated Bill, matters involving State security will usually be heard at secret ‘closed material procedure’ hearings. They will be attended only by security-vetted ‘special advocates’. Those involved in cases against official bodies will be permanently unable to know about the evidence deployed against them.

Ian Paisley Jr: Cast the critical vote.

The new revised draft, the product of the final session of the Bill’s committee stage, was forced through by a majority of one. The Ulster Democratic Unionist Ian Paisley Jnr cast the critical vote.

This took place at precisely the same time as the same-sex marriage debate was happening in the main Commons chamber, which is why all this went virtually unnoticed.

The consequences are draconian. The Government’s actions, prompted by intense lobbying from MI5 and MI6 security chiefs, mean there is now less than three weeks to stop the enactment of a ruthless measure that amounts to a charter for cover-ups.

A real recent example of a case that will be affected is that of Abdel Hakim Belhadj. He is the Libyan opposition leader abducted with his family from Bangkok with the help of British intelligence, then  tortured by Gaddafi’s brutal regime for years.

Like other victims of ‘extraordinary rendition’, Mr Belhadj,  who has never been alleged to have committed a single hostile act against Britain, its citizens or its allies, is suing the UK Government. But the official evidence of what was done in our name will be deemed far too ‘sensitive’ to be aired in open court.

Once the Bill becomes law, his chances of success are remote. And the prospects for enforcing the merest whiff of accountability on the agencies responsible for torture cases, and, indeed, a vast range of official activity from national security to the country’s ‘economic wellbeing’, will be just as distant.

Previously, the Lords had passed two crucial safeguards to stop this. The first said judges could grant the Government a secret hearing only if other alternatives had already been considered, like, for example, asking permission from the judge in a case to withhold sensitive evidence altogether, under the longstanding system of ‘public interest immunity’. The second Lords safeguard was more fundamental.

It stated that judges could allow a secret hearing only after balancing the Government’s demand for one against the historic legal principle that justice must always be open.

Last week, with the passage of Amendment 55, moved by the junior Justice Minister James Brokenshire, both these safeguards were swept away. ‘In practice, it will now be very difficult for a judge to resist a closed hearing,’ one legal analyst said yesterday.

Under this Bill, it is now possible a prisoner in a British jail who tried to challenge his detention in the courts would remain incarcerated without hearing the evidence against him.

The battle is not over. Pending is a High Court action by The Mail on Sunday which seeks to make public a secret judgment issued in an Afghan alleged torture case two years ago, which resulted from an earlier form of secret hearing, now deemed illegal by the Supreme Court.

As this newspaper has pointed out, the Bill will inevitably lead to a body of secret law and secret legal precedents. Our case also asks the court to issue guidelines on how such secret judgments should be reviewed, and whenever possible, published.

Meanwhile both Labour and several influential Tories are determined to try to reinstate the Lords’ safeguards when the Bill returns to the full House of Commons later this month.

David Davis, the leading Conservative backbencher, said: ‘It is appalling that the Government has reneged on its promise to allow full judicial discretion as enacted by the Lords.’

Andrew Tyrie, the Tory who campaigned for years against torture and rendition, says: ‘Not only must all of the Lords’ amendments remain in the Bill, they need to be underpinned by further improvements.’

Mr Davis added: ‘What the Government did last week is a massive dilution of the protections put in place by the Lords. I can only hope they will summon up the courage to reinstate them.’

It is a hope anyone with even the vaguest interest in open justice would surely share.