I don't see this so much as a free speech issue as an issue about lying. I don't think it is unreasonable to say that in countries such as Austria, if you're going to talk about the historical record of WW2, you have an obligation to do so accurately. Irving is entitled to whatever opinions he wants, but he's not entitled to his own set of facts, and I think it's acceptable to call him on that difference.First of all, you can't perjur yourself outside of a courtroom. So I think that comparing this to perjury is really not appropriate.
We send people to jail for perjury, after all. Why is this so different?
As to whether he is entitled to his own set of facts, I think it's fair to say he is, and so are we all. Religion in general is a good example of this: people are free to say (and believe) that Adam and Eve rode dinosaurs to church, even though that's totally absurd and untrue.
I think a good analogy that demonstrates the problem with passing a law against Holocaust denial is the idea of Congress passing a law in the US that made promulgating ideas supporting climate change or evolution a criminal act. George W. Bush and not a few other legislators are not at all convinced that climate change is occurring, or that human beings are the cause of climate change. The entirety of the scientific community disagrees with them, but they're not the ones in charge. Ignoring signs of climate change may be just as or more dangerous than the Holocaust was, in terms of harm to human beings, but we're not locking energy executives up for denying the impact of humans on the Earth's climate.
Not only is it dangerous to go around passing laws about how to interpret the facts of the world around you (or which facts it's okay to ignore), it is beyond the scope of the law to legislate what is and is not reality. You cannot legislate something into being true, and you certainly can't legislate facts so that people will believe them. Congress cannot repeal the law of gravity, and it cannot enforce the reality of climate change or of the Holocaust. There are a lot of things that politicians say about science or history that are, in my estimation, complete bunk. I'm a trained scientist and know more about biology and chemistry than the guy in the White House, but I don't have the power here. Laws like Austria's have too big a risk of not being on the right side of history or reality.
I think Irving is a cretin, and on a purely gut-level, I am glad he's in jail: he deserves it. I'm also sympathetic to Austria's position - they can't be the birthplace of another Hitler, and neither can anywhere else in the world. The world can't afford it. Still, passing laws against ignorance simply can't work in the favor of a society that wishes to make intellectual progress. It's not just luck that dictates that Irving's claims don't hold up to scrutiny in any way, and he's not even so committed to his lies that he won't abandon them when the going gets tough. Having the real world on your side is very helpful when it comes to combatting a guy like this.
I am not willing to trust my government to enforce reality. We've already had enough trouble with an administration that scoffs at the "reality-based community," because they have enough power to effectively crush any kind of doubt about the neoconservative vision of the world. There are dangerous ideas out there, and Irving's are amongst the most dangerous, but there is greater danger in manufacturing a "reality" than there is in verbally and continually shooting down a moron who makes up insidious lies.