Sharia Courts and legal pluralism

There's an interesting article by Clive Coleman in the Saturday Times about Sharia courts and the effect that they're having on Britain's legal system.

He mentions the fact that unlike our Batei Din, Sharia courts are extending into criminal matters. He sees this as no cause for alarm:

We allow organisations such as schools to administer their own justice. Schools often deal with an assault by one pupil upon another, clearly a criminal act, without involving the police. We are largely content to let them do so, perhaps because they are tacitly licensed in that behaviour by the State.

But there's a big difference between common assault and a serious crime such as rape or drug dealing. An unofficial Somali court recently heard the case of a group of youths accused of stabbing a fellow Somali. Witnesses and families were brought together for a hearing in which the men admitted their guilt and their fathers and uncles agreed compensation for the victim.

Critics of Sharia courts like to argue that they will lead to beheadings and amputations. It goes a lot further than that. If a stabbing can be excused by a simple matter of compensation, what's to say that a Sharia court won't let a murderer off with blood money?