When I was a student of law in the Allahabad University, I had read of the British Constitutional principle "The King can do no wrong". At that time I did not understand the significance of this principle and what it really meant. It was much later, when I was in law practice in the Allahabad High Court that I understood its real significance.
The British were experienced and able administrators. They realized from their own long, historical experience that while everybody should be legally liable for his wrongs and made to face Court proceedings for the same, the person at the apex of the whole Constitutional system must be given total immunity from criminal proceedings ,otherwise the system could not function. Hence the King of England must be given total immunity from criminal proceedings. Even if he commits murder, dacoity, theft, or some other crime, the King cannot be dragged to Court and made to face a trial.