Fruit machines are one of the most addictive forms of gambling, so this decision is deeply worrying. Of all the different types of gambling, it is fruit machines that act as a “learning device”, where people get hooked on the idea of gambling.

Once they are addicted, they often move on to other kinds, particularly online gambling, and try to recoup their losses.

I'm not against gambling — I do it myself. But it is a highly addictive activity and public policy needs to encourage moderation. To increase the prizes is definitely not in line with the stated purpose of the Gambling Act: to limit problem gambling.

The size of the prize undoubtedly increases participation — the best example is what happens in the National Lottery, when a rollover produces a tremendous increase in the number of people who take part.

Greater participation will nudge some people who were not gambling addicts closer to the edge.

Each time there has been a change to the gambling laws since the Gambling Act was passed it has become easier for the promoters to make more money out of the punters.

I think the Gambling Commission has not been as tough as it ought to be. It is generally recognised that the success or otherwise of the Gambling Act is very much determined by the commission's approach.

This is illustrated by the commission's reaction to the prevalence study, which determined the levels of gambling in Britain. That showed that fixed-odds betting terminals, spread betting, betting exchanges and online gambling have a high incidence of producing problem gambling.

The commission's reaction, however, was that one could not draw any conclusions about “causality” from this. It has adopted the view that unless the evidence of harm is utterly obvious, it is going to turn a blind eye.

It has not shown itself to be the kind of watchdog that it ought to be.

Dr Emanuel Moran is specialist adviser on pathological gambling, the Royal College of Psychiatrists

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