Officially called the Community Charge, it replaced the "Rates" – a system of local government taxation based on the estimated rental value of a house. It had been around in some form since the start of the 17th Century.
Mrs Thatcher decided instead on a flat-rate charge for every adult, earning her new levy the nickname "poll tax" as a result. It was a decision that would contribute significantly to her downfall.
The tax was seen as deeply unfair, a common argument protesting that a millionaire and his cook would pay the same charge. It was a tax on individuals regardless of their means. An opinion poll at the time showed that 78 per cent opposed it.
With seven days to go before its introduction up to 250,000 people turned up in London to protest while many smaller rallies were held across the country.
The trouble in the capital flared when a group of protesters, sitting in Whitehall close to the entrance of Downing Street, refused to move when told to do so by the police. As arrests were being made placards and cans were thrown from the crowd.
The disturbance then quickly spread to Trafalgar Square, which became a battleground, and surrounding areas. It escalated into savage violence on both sides, the baton-wielding police being attacked with bricks, cans and pipes. Shop windows were smashed, overturned cars were set alight and much of central London was cordoned off.
By the end of the day 113 people had been injured, 45 of them police, and 340 protesters had been arrested.
Later that year Mrs Thatcher was challenged for the leadership of her party by her former Environment Secretary, Michael Heseltine. Although she defeated him, she did not win enough votes to prevent a second ballot and, pressed by her closest advisers, she resigned, fatally undermined by the poll tax.
Her successor, John Major, took over as Prime Minister, scrapped the Community Charge and replaced it with a system similar to the Rates, once more based on property value.
When Mrs Thatcher stepped down opinion polls showed that just two per cent of the public supported the poll tax.
Published: March 4, 2018
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