Intrigued by the brother-in-law quote thing, I actually made an attempt to confirm my recollection about the 1960s English political novel which used it.
Found the Edelman books in Manchester Central Library. Skimmed them only - both seem turgid now. Almost certainly, neither is the one I was thinking about. The Minister is all about The Winds of Change, but deeply serious. The Prime Ministers Daughter centres, intriguingly, round an honours scandal concerning a newspaper proprietor, & press harassment of the PMs vulnerable daughter. Plus ca change, indeed.
Thought to leave it at that - one doesnt want to get too obsessed about trivia. But then another name dragged itself out of the fog of memory. David Walder, another 1960s novelist MP
How many novelists sit in the House of Commons today? **
It sounds more Walders style perhaps. But no local library - not even Manchester- seems to have any copies of the books, so that is definitely that.
But at least the dates show that Martin Luther King used the quote before either novelist (Oxford Dictionary Quotations has it 10 September 1962, in NY Journal-American). Wonder if either of them pinched it from him? Or if it was just a common saying at the time?
And - think very hard about this - why does an American commentator (Drew Weston) writing in the 21st century think that this was a shrewd political move on Kings part, but an English novelist of the 1960s could see in it the potential ruin of a political career?
**At least two. Ann Widdecombe & Iain Duncan Smith!