The problem of sharia arbitration in Britain:

Contrary to popular belief, there is no central network, no supreme sharia judge, no sharia bar, no sharia AGM, no sharia ombudsman, no sharia HQ and no torts [...] Sharia law isn’t even written down and most Muslims will dip in and out of it when it suits them.

I don’t know about the other details the writer highlights. It seems like a complaint about the ’social pressure’, something which is hard to define. Trying to use the blunt instrument of the law against something like being shunned from your community’s peers would be disastrous.