They also did it in 1981, but far more blatantly, in the days of the Greater London Council (GLC).
Labour was elected to control that body with Andrew McIntosh at the helm. A vigorous campaign was fought by the Tories, who insisted that the �moderate� McIntosh would be deposed after the election. This was strenuously denied. The Tories lost and just one day after the election the council voted themselves a new leader, who went by the name of, er.... Ken Livingstone!
Mrs Thatcher successfully abolished the GLC in 1986 and London functioned perfectly well for fourteen years. However, this ridiculous government sold the idea of an �elected mayor� to the gullible London electorate along the lines that they would get a mayor rather like New York had in Rudolph Guiliani.
All they got, of course, was a resurrected GLC (now called the GLA) which was put in place to satisfy the government�s masters in Brussels who want to see the UK reduced to a number of manageable (i.e. easy to bully) �regions�.
What Londoneres really need every four years is not a choice of political and social misfits who try to run their vital services in line with their own ideology. They need instead an option to say whether they would continue to prefer to have a mayor at all. They should also be asked whether they would like to continue to pay for the mayor�s �small number of administrative staff� (which was what they were told they would be getting in 2000, and whose numbers currently run to about 700), or whether they would prefer their services to be run by professionals in the relevant fields.
Will this happen? Not until a squadron of pigs takes off from �London� Biggin Hill aerodrome (which is 20 miles from central London, in rural Kent, but over which the Mayor and the GLA hold power to determine what it can and cannot do).