There is no such thing as diplomatic immunity or royal immunity in Islam. Everyone is accountable to each other, and even if they get away with acting with impunity in this life, they will be answerable to Allah, just like the rest of us. The only being that is beyond questioning is Allah.
Something is causing confusion within the ummah at the moment, and we can summarize it as the commercialisation of Islam. It happens on different levels, and while people can complain that this is not adherent to Islam, the truth is that this ship has sailed a long time ago.