People are coupling and decoupling all the time in Great Britain. The fact that Muslims choose to precede it with a certain formula of words, shouldn't bar them from anything. But, no one's saying that polygamy should be institutionalized in this country. That Muslim's uniquely should be allowed to have two or three or four marriages.

I was a teenager when General Zia took power in the Pakistan; I was in my twenties when I went there during the late 1980s and I saw then not only the novel punishments that he was introducing - because they were novel, and this is again something that's very important to understand, it's only in the last thirty, forty years, since 1979 in fact, that these penalties have been revived anywhere in the world apart from Saudi Arabia.

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.

Whereas a man is entitled to marry three more times and that fosters great abuse, even scholars accept that. So certainly since the 1980s Shari'a courts have been established and they allow for women to go to them and they basically grant them annulment. It's not a civil divorce, they don't have the right to grant alimony or maintenance or custody.

The first thing to say is that the ordinary criminal law in this country, the Human Rights Act, the Children's Act, all of the laws of the country take precedence, but what I'm also saying is that within the context of a secular country, which Britain now kind of is, or at least a country which purports to be relatively equal between religions, there should be some scope for allowing faith communities to govern themselves - subject to it being consensual and subject to everyone's human rights being observed.

There is an issue about the discrimination provisions because the Qur'an does say that women should have half the share of men. Again, in the seventh century perhaps that kind of made sense, but in the twenty-first it very often doesn't. But in the arbitration contract that won't arise. An inheritance dispute might arise after someone dies but the two sides have to come together consensually.

The first rules about Islamic law weren't even written down for a century and a half after the Prophet's death, and it was another five centuries, half a millennium, before they assumed anything like a definitive form. So there have always been huge arguments over what Islamic law actually requires. There are four main schools of law in Sunni thought and there's a separate school of law in Shia thought, so these arguments do take place.