Surely we all know that the shell game is a sham? Not in this city of shills

"The hapless tourists are, I feel certain, prey to exactly the same psychological hoodoo as the MPs."

Saturday afternoon in central London is my favourite time and location for observing the madness of crowds. In particular, I prize the purlieu of Westminster Bridge, because it is here, in the sickly sweet aroma-cloud of caramelising peanuts and to the accompaniment of a torturous bagpiper, that the great mass of tourists iPads its way between the dubious cultural delights of the South Bank and the more solid sights of the abbey.

A cynic would see in these milling masses evidence only of robust German household saving; for, were it not for the artificially high level of the euro against the pound, the vast majority of these trippers would be scattered to the four winds, leaving the pavements empty except for the mournful flap-slap of discarded plastic Union Jacks.

I am that cynic and while it’s true that this flock of marginal-preference sparrows might, soon enough, alight on the Ramblas in Barcelona or the Kurfürstendamm in Berlin, neither of those locations presents quite such a perfect picture of deceit being wreaked under the nose of power. Right in the shadow of Portcullis House, you can happen upon not one or two but perhaps five or six separate teams of con artists perpetrating the shell game on unwary dentists from Oporto and guileless Dutch computer programmers.

The shell game is one in name only. The crowds that gather around the men who manipulate the three cups – or “shells” – atop boards lain on the pavement mostly comprise shills whose task it is to pretend to bet on the whereabouts of the hidden “pea”, a small, soft ball that is allegedly underneath one of the shuffled cups but in reality is usually up the prestidigitator’s sleeve. The unwary mark is lured into their midst and there she sees one of the shills either win magnificently or lose pathetically – in either of these cases, her blood up, she is emboldened to put down an extravagant “bet”, which soon enough disappears.

I bunged my man at the Met a few euros to find out what gives re: this flagrant taking and he came back with the intelligence that while the constabulary does occasionally roll up the shell-gamers, it’s only a matter of time before they’re back on the bridge. Anyway, even if one or two are nicked, the great strength of the con artists lies precisely in their strength . . . of numbers. Forming a crowd-within-a-crowd, they have watchers fore and aft, ready to alert their confrères should there be any prospect of bother.

I cannot forbear from observing that there are close parallels between the exactions of the con merchants outside parliament and those in the lobbies. In both cases, the punters are being offered a large reward – cash or a government sinecure – while being jostled in a confined space. In the MPs’ case, they’re an easy mark for the duplicitous whips because all sorts of situational cues – red leather benches, John Bercow, despatch boxes and so on – lead them to believe they are taking part in a “democracy” and so they’re happy to divvy up what’s left of their hard-won convictions.

The tourists are far more difficult to understand. I mean to say, who in 2013 can possibly have reached adulthood without being aware of the shell game? I sometimes ask myself, “Are these crowds of Kaspar Hausers?” – so devoid do they seem of the commonest sense. Yet the truth is at once far more disturbing and far more prosaic.

No, the hapless tourists are, I feel certain, prey to exactly the same psychological hoodoo as the MPs. Sans doute they have heard of the shell game and bien sûr they know that it’s used by unscrupulous types to part fools from their money – but such a heinous scam couldn’t possibly be perpetrated here, in the heart of London. For, since childhood, they’ve been acquainted with the well-known British sense of fair play and they’ve read about our storied constitution – a model of divinely organic and cosmically just evolutionary adaptation; they’ve also seen films in which the incorruptible British bobbies crack down hard on any wrong doers, although only with a big wooden stick.

So, looking first up to the great clock face on the newly named Elizabeth Tower and then down to the three shells and hearing the deep, resonant, BBC-bong! of Big Ben over the chatter of the “gamers”, they are entirely persuaded that while one or the other of these phenomena might conceivably be a sham, it is quite impossible that all of them are.