To suggest the Shari'a Courts in the UK are a parallel legal system is mischievously misleading and takes advantage of the public's ignorance.
A court can only impose itself because it is an apparatus of the state. It imposes by using others apparatuses of the state: the police force and prison system.
Do you see UK Shari'a Courts using the police or prisons to run a parallel legal system? No!
So stop peddling this propaganda which serves two purposes:
1) radicalise wider UK public against the term Shari'a and 2) intimidate Muslims against their confidence in Islamic legislation.