One of the big problems in this field is that there's so much mystification that surrounds talk of the Shari'a, whether its saying that Islam is all about peace or whether its people saying that Islam is all about Jihad and all about suicide bombs. People will make statements which don't seem to be backed up by any sort of historical context.

There's crucial distinction that has to be drawn between the Shari'a, which is this hugely expansive vision of cosmic order that I've been describing, and principles of Islamic law, known in Arabic as "Fiqh" - a word that means understanding. If you're a devout Muslim, you don't argue against the Shari'a; the Shari'a is the path that God has laid down. But what you can do, and what people are doing all the time, is arguing over the correct interpretation of the Shari'a, arguing over the Fiqh. That's something that has been going on throughout Islamic history.

I think there's a real danger that Islamophobia can actually be a cover for something far more malign. I don't want to sound like a spokesman for the Muslim Arbitration Tribunal but I am a supporter of autonomy for religious communities and for non-discrimination.

Ayatollah Khomeini issued a fatwa to that effect, which was then given effect in the Islamic Republic of Iran, so in the Islamic Republic of Iran, it's flexible enough to allow for sex changes, and it encourages sex changes. But if you want to change your religion in Iran, you've got some serious problems. There are other problems. You're allowed to change sex, but if you want to be a homosexual, theoretically at least, you face the death penalty. Quite how often these penalties are carried out is a moot point, but it's there on the statute books.

The politicized version of Shia Islam that we see in the Islamic Republic post-1979 clearly is very conservative, but, there are other things one could say about Ayatollah Khomeini's concept of a Shia state because that in itself is a blasphemy as far as most Shia clerics are concerned. There's a theory that he developed in the early 1960s in the town of Najaf talking about - well not liberalism, necessarily, but flexibility though.

There were periods in Islamic history when things like apostasy and blasphemy were made punishable. So you know it kind of depends - there's no argument, quite apart from the question of the divine or otherwise nature of the Qur'an, that huge swathes of Islamic law are man-made. Clerics here - in maintaining their power, will often try to elide that and say "Well no, actually this isn't man-made at all. Stoning is part of the divine revelation." It isn't in the Qur'an but the way this has been done over the years is to take the Hadith.

My background is such that I am uneasy about religious laws, I think there's always a real danger when you start appealing to a higher authority. It's self-righteousness, it's not righteousness, it's self-righteousness that takes control. But I think that it's absolutely crucial that that's not confused with the debate that takes place over Shari'a law in Great Britain at the moment. Because as far as anybody is concerned, when you talk about Shari'a courts now you're talking about - I don't know what people think.