Leading article: Free speech, responsibility, and the right to dissent

Mr Irving is known as a right-wing historian of Germany. He has spent much of his adult life claiming that there was no systematic extermination of Jews by the Nazis or, if there was, that many fewer died than is generally accepted. It was the articulation of these views in 1989 that got him into trouble in Austria, precipitated his arrest when he re-entered the country last year and led to his trial and sentencing yesterday. To us, though, this case is far less straightforward than the Vienna court proceedings would suggest. We hold no brief for Mr Irving's views on German history; as to his overall philosophy, we could not disagree with him more. But he is entitled to hold the views he does, and to express them in public.

The principle of free speech cannot apply only to those who hold views with which we agree. But neither, as we have seen with the Danish cartoons, can it be a shield behind which those who, knowingly or not, give gratuitous offence to others can hide. Nevertheless, everyone should be able to believe and say what they like, up to the point where their words amount to incitement of hatred or violence or murder. Disputing the Holocaust, of itself, does not come into that category, however erroneous and hateful such an opinion might be.

Which is why we have deep misgivings about the classification of Holocaust-denial as a prosecutable offence. We understand why Austria, in common with Germany and half a dozen other European countries, as well as Israel, should have such a law on its statute book. It stands as a perpetual reminder of the past and as a declaration of intent, enshrined with all seriousness in the legal instruments of the state, that nothing like the Holocaust will be allowed to happen ever again.

And it is arguable that Austria, which was never called upon to purge its Nazi past as profoundly as was Germany, still has need of such a law. At any rate, its penalties for Holocaust denial are among the severest there are. It is also true that there is often more to Holocaust denial than simply disputing the historical fact that the Nazis systematically murdered Jews (and Slavs and homosexuals and others). Denial that the Holocaust happened may be little more than a cloak for anti-Semitism. We have absolutely no sympathy with either.

We would argue, however, that laws restricting free speech are not the way to deal with Holocaust denial. As a historian and a private citizen, Mr Irving is entitled to believe what he pleases, however deluded or unsubstantiated that may be. He should also be able to say what he believes on a public platform. To prosecute Holocaust denial is the start of a slippery slope that ends in the proscription of all dissent. And dissent can be defined as anything which at a particular time displeases those in authority.

Yesterday, Mr Irving astonished the court by announcing that he now accepted the historical fact of the Holocaust, having read the personal papers of Adolf Eichmann. At worst, this was a ploy calculated to minimise his sentence. At best, it showed that the historian - for all his vile opinions - was still scholar enough to be swayed by documentary evidence. As repressive states have shown down the ages, minds are changed not by persecuting those who hold inconvenient views, but by exposing them to experience and to facts.