] The story goes that a Windsor farmer accosted the King in on eof his fields and accused him of trespass (i.e. crop damage) and got an apology from him.

That is very well. It is a entirely within the very strict English sense of property rights. Every man is king on his own land.

Do you remember where you heard this?

] And, of course, there's William Beckford Snr, Lord Mayor of London, who told the king he was a twit in public; the result of this action being that Beckford's statue was erected in the city

Was this the author William Beckford or another one?

Actually these are probably still serious offenses in the Empire. The Canadian Criminal Code lists section 49 "Alarming her majesty" as an inditable offence. My class all had a good laugh over that one in Criminal Law.