Opinion poll chief warns about false election 'leaks'

Robert Worcester, chief executive of MORI, the opinion pollsters, has written to John Kemp-Welch, chairman of the London Stock Exchange, urging him to clamp down on insider dealers who manipulate share prices by "leaking" non-existent poll results in the run up to a general election.

The letter has raised eyebrows in the City, where some attributed it to publicity seeking on Mr Worcester's part. Others were perplexed at the suggestion that, this time round, it would make any difference at all to the share prices whichever party won the election. If anything Mr Blair seems to be to the right of past Tory premiers like Edward Heath and Harold Macmillan.

Mr Worcester writes that City commentators have already said that during the election campaign the stock market will be buffeted by the fortunes of the political parties as measured by the opinion polls.

He says he does not worry about this, as information will always drive share prices, whether the announcement of economic, employment or other statistics.

"What I do worry about is the rumours of results of private polls, or worse, fictitious poll findings, leaked out by unscrupulous traders in an effort to manipulate the markets. In my view, the Stock Exchange should be concerned about this."

Mr Worcester says he wrote to Mr Kemp-Welch's predecessor Sir Nicholas Goodison in 1979 about this problem.

"In that election over 100 telephone calls were taken by the Daily Express and oursleves about rumours of a 'last minute swing to Labour', reportedly showing a 2 per cent Labour lead, coming out on the Tuesday before the election."

Mr Worcester writes that some pounds 1bn in the value of shares was wiped out by these rumours of a poll which never existed. Later it was rumours of a Gallup poll in the Telegraph - equally non-existent - which caused City traders to panic, he writes.

City sceptics might argue that it is difficult to see anyone "panicking" whatever the result of the present election.