After every major public rally in London there is a debate about the number of people who took part.
The organisers will claim one figure, the Metropolitan Police will estimate another (usually smaller) number, and the BBC will do what it always does - report uncritically (and without evidence) the larger ‘estimate’.
Yesterday’s ‘People’s Vote’ march is a prime example.
The following, written by me in the aftermath of a TUC rally in 2011 that was said to have attracted up to 500,000 people, is as relevant today as it was then:
I have very good reason to be sceptical about this estimate. In October 1983 I stood on the roof of an office in Whitehall which gave me a bird's eye view of a CND march in London. According to the BBC, it was estimated that one million people took part in the march and subsequent rally in Hyde Park. Bizarrely this was far greater than even CND's estimate of 400,000.
They were both wrong. The group whose roof I was standing on belonged to an anti-CND outfit called the Coalition for Peace Through Security (CPS). Julian Lewis, who was director of CPS and is now MP for New Forest East, takes up the story:
"The Campaign for Nuclear Disarmament had, in its time, managed to rustle up more shouters on the streets than most: it turned out about 150,000 and 100,000 in 1981 and 1982 respectively, and characteristically claimed a quarter of a million on each occasion.
"In order to frustrate yet another such cavalier exaggeration in October 1983, the Coalition for Peace Through Security commissioned an expert photographic analysis which showed the true figure on that occasion to be approximately 98,000 for march and rally combined.
"So as to show 'progress' on their own grossly inflated estimates for the previous two years, the CND had felt obliged to claim 400,000 – a total ruled out as absolutely impossible by our aerial survey."
Without a similar survey I don't know how anyone could estimate accurately the number of people at Saturday's rally, but you can be sure that neither the TUC nor the BBC will have erred on the side of reality.
In the case of the People’s Vote march you can be equally sure that the number that took part yesterday is nowhere near the figure being estimated by organisers and reported by the media.
In any case the only number that counts is the 17.4 million people who took the time and trouble to vote Leave in June 2016, thereby winning a referendum whose outcome the government promised, in advance, to uphold.
Can me old-fashioned but I believe it’s called democracy.