BRITISH super-casinos are to be banned from using Las Vegas-style psychological trickery to entice customers to part with their cash, The Times has learnt.

Tessa Jowell, the Culture Secretary, has taken fright at some of the mercurial tactics used by Las Vegas casinos to keep customers anchored at slot machines hour after hour.

Tricks include removing clocks from the gaming floor so punters lose track of time, simulating daylight at night and pumping pheromones at slot machines to encourage faster and more aggressive betting.

In response, the Government wants to introduce safeguards against Las Vegas-style manipulation in Britain’s eight super-casinos. The first is expected to open in around 2010 if the Gambling Bill becomes law. The controversial legislation returns to the Lords for a committee session this Thursday.

Ms Jowell told The Times: “British casinos will be quite different to those overseas. They will have to act in a socially responsible way and will be tightly regulated. They will be run according to British rules and we’ll simply not allow any tricks which people are subjected to unawares and which increase the risk of problem gambling.”

The Government has already announced that free alcohol will be banned from gaming tables, and “comping” — an incentive system that keeps customers betting by offering free hotel stays, room upgrades and meals — will also be forbidden.

The Gambling Commission, which will regulate the betting and casino industry, is responsible for enforcing the licensing conditions. Companies which break their licence conditions face unlimited fines or the possibility of closure.

In recent years international casinos have become laboratories of behavioural science, where nothing is left to chance, from room temperature to the colour of the machines. Even birds are scared from the trees in Las Vegas by ultrasonic bleeping to prevent them from messing on the pavements.

Many psychological technologies are easy to spot. Harrah’s, which is hoping to build a casino in Birmingham, spends tens of thousands of dollars a year studying whether wider aisles, fresher air and even back supports on slot-pit stools will keep customers in place longer.

Colouring of slot machines, for instance, is considered crucial. Machines at the ends of rows are brightly coloured, predominantly red, and tend to pay out frequent small sums. The tactic, known as “positive reinforcement”, was introduced after an American researcher, B. F. Skinner, discovered that it increased motivation.

Background noises are carefully controlled to make sure that there is the near-constant sound of coins hitting a metal collector.

Most slots have “one-armed bandit” handles to increase the player’s feeling of having a role in the outcome. In fact, the position of the reels is determined by a computerised random-number generator set inside the machine.

Other forms of manipulation are more subtle. All casinos ensure that the environment and temperature are carefully controlled, though companies deny pumping fresh oxygen to keep people awake.

Scents have been tried. In October 1991 Alan Hirsch, a Chicago neurologist, sprayed a pheromonal scent, Odorant 1, for 48 hours around 18 slot machines at the Las Vegas Hilton, at the casino’s invitation. The “drop” — money inserted — in these machines was 45 per cent higher than normal. According to documents seen by US News & World Report, at least five casinos subsequently began to pump Odorant 1 into their gaming rooms, though the Las Vegas Hilton decided against it.

Other techniques could prove harder to ban. Casinos in the US collect a myriad of information about their regular clients.

The US News investigation revealed that an unnamed Las Vegas casino kept details of their regulars’ exact losses, average bet, time spent gambling, “average worth” (how much they should lose based on time and probability), height, weight, hair colour and whether they needed glasses. Casinos now track their regulars using biometric technology, with computers identifying them from CCTV.

Over the weekend, Ms Jowell warned critics of the Gambling Bill of the consequences of blocking the legislation. “I think it is good legislation and it is urgently needed so the unregulated parts of the industry are brought under clear regulation,” she said.

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