There is a very good reason why lawyers are concerned at the government’s Criminal Justice Bill, which includes abolishing some trials by jury, allowing gardai to give opinion evidence and holding detention hearings in secret without accused persons or their lawyers present. The reason is that such provisions are serious assaults on civil liberty and the due process of law, and are not acceptable in an advanced democracy.

Civil liberties exist to protect individuals against the arbitrary use of state power. They include rights to individual freedom, privacy, the secure possession of private property, the expression of opinion without prior restraint, the holding and exercise of personal beliefs, and more.

Central to civil liberties is the idea of a due process of law, a set of procedural formalities and restraints which protect the innocent, assure equal treatment and require the authorities to show good cause why they exert state power over citizens, not least the powers of arrest and detention. Tyranny exists wherever civil liberties do not. Think of a typical police state such as Soviet Russia in the period of its worst excesses, where men knocked on doors in the night and took people away to torture and imprison without trial because there was no regime of civil liberties, no institutionalised protection for human rights, to stop them.

The modern democracies of Western Europe are, of course, a long way from being tyrannies, but from Germany to Ireland too many of them are going down the alarming road of compromising civil liberties in the supposed interests of fighting terrorism and crime.

Authorities in all countries and at all times, even in Western democracies, find themselves inconvenienced by civil liberties, which make the job of policing society more difficult. In particular, and to the great irritation of governments everywhere, civil liberties interfere with authorities’ ability to detect, arrest, prosecute and convict bad people. But there is a good reason why civil liberties make the work of the authorities more difficult: to protect the great majority of people who are not bad. The inconvenience of the authorities is the freedom of the people, and it is a price worth paying.

The civil liberties which until now have served to define the open democracies of the Western world are taken for granted until something like the Criminal Justice Bill comes along to call them into question.

People forget how hard it was to achieve these civil liberties in the first place. It took centuries of struggle. Think of what had to happen in order for the ordinary 21st century Western citizen to attain the position of a free citizen whose rights are protected by law.

The process began in the 16th century Reformation. First, the hegemony of a single church over the minds and lives of individuals had to be broken. Then absolute monarchy had to be challenged and replaced by more representative systems of government. Both processes were sometimes revolutionary but mostly evolutionary.

They were painfully slow and difficult because of the reluctance of those in power, both ecclesiastical and temporal, to give anything away. Many died in furthering the cause of liberty — at the church’s stake, in chains in royal dungeons, on the battlefield.

It is astonishing to think that the ordinary citizen of a democracy today enjoys rights, freedoms and possibilities that a few hundred years ago were only available to very few: to aristocrats and senior churchmen. We are all aristocrats now in the degree of our liberties and opportunities, because we have replaced the rule of might with the rule of law.

No arbitrary ruler can throw a citizen into prison at whim; institutions and practices buttress the individual’s liberties. Among them is trial by jury, the need for proof to be brought before a court where it can be tested properly, and a presumption of innocence for anyone accused of committing crimes.

Any society which goes into reverse because it is facing hard times betrays the long history of struggle. The test of a society’s strength and maturity is whether it can stick to its principles in the face of difficult challenges.

The question Ireland faces in the battle over Dermot Ahern’s bill is whether it will betray its principles or show strength and maturity by defending them.

AC Grayling is professor of philosophy at Birkbeck College, University of London. His most recent book is Liberty in the Age of Terror, published by Bloomsbury.

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