Margaret Thatcher received a warning to pay up her own hated poll tax

Documents released by the National Archive show the Tory PM was warned she faced a fine for not registering

National Archives release

Margaret Thatcher was threatened with a fine for failing to register for the hated poll tax which triggered her downfall, documents reveal today.

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The Prime Minister was warned she would be in breach of the law unless she completed her registration form on time, according to newly-published files.

The poll tax, officially called the community charge, was seen as Mrs Thatcher's biggest policy bungle during 11 years in power. It triggered riots and led to her leaving Downing Street in tears after being dumped as Tory leader in 1990.

Early the previous year, local authorities in England and Wales began issuing poll tax registration forms. One form covering 10 Downing Street, which Mrs Thatcher and her husband Denis had nominated as their main home, was sent to the Treasury.

But the Cabinet Office complained that it was "most inappropriate" to issue a single form "asking a number of essentially personal questions" on behalf of individual occupants. Separate forms were sent out, but when there were still no details forthcoming, the Westminster City Council registration officer, David Hopkins, warned he would be forced to act.

In a letter dated May 22, 1989, he wrote: "My records show that the Community Charge Registration form recently sent to you has not been returned. "I wish to advise that you are required by law to supply the relevant information within 21 days of this request and failure to do so may lead to a penalty being imposed."

Panicking officials quickly arranged for Mrs Thatcher to complete the form, only to discover the council had sent the wrong one and she had to do it all again. The arrogant premier chose to shrug off the bureaucratic blow, claiming her first effort had been "a good practice run".

The poll tax was brought in to replace the old system of rates, based on property values, with a flat-rate levy on all residents. Mrs Thatcher hoped voters facing much higher bills would blame Labour councils who tended to spend more on providing services. But her cynical ploy backfired. When poll tax demands started dropping through letterboxes across the country – including in many traditional Tory areas – central government came under fire. There was a wave of protests.

The shocked PM was left bewildered by the reaction, according to papers released by the National Archives in Kew. In March 1990 she told Chancellor John Major she had always assumed the public would blame councils for any rises. "But in recent weeks that has not happened," she moaned. "Rather the general public blamed the high levels of community charge on the government because of their responsibility for introducing the new system."

She admitted that, with those on low incomes protected through "safety net" measures, it was the "conscientious middle" – traditionally her strongest supporters – who were being hit hardest. Mrs Thatcher ordered a "rapid review" of possible changes for the following year, but the political damage had been done.

On March 31, 1990 – days before the tax was due to come into effect – a mass march through central London unleashed some of the worst rioting in the capital for decades. Trafalgar Square became a battle zone, with mounted police clashing with furious protesters. Metropolitan Police commissioner Sir Peter Imbert told the Prime Minister some of his officers "came close to being murdered".

It was Mrs Thatcher, however, who was fatally damaged politically. By the end of the year her Cabinet colleagues had knifed her and she was out of office.

Where are Britain's highest tax bills?

Where are Britain's highest tax bills?

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