Some people claim that due to various clauses in the Marriage Acts of 1949 and 1953 that members of the British Royal Family can't contract a legal marriage in a civil ceremony, in England, but the highest legal official of the government, the Lord Chancellor, has advised otherwise. Unless a court rules differently, which personally I doubt that they will now but who knows with courts, then the marriage is legal and Charles remains the heir to the throne with Camilla to be his official consort. There is a minister of the Church of England who has put in a number of protests about the marriage and he may take the matter to court but unless the court rules the marriage illegal it is legal.