In 1935 London's regional planners proposed the Metropolitan Green Belt and the 1947 Town and Country Planning Act encouraged local authorities to protect the land around towns and cities from building.

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The prosecutions were pursued privately by the council under Section 178 of the Town and Country Planning Act in which it as an "offence to wilfully obstruct" a local planning authority taking enforcement action.

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The justices ruled that there had been no change of use within the section of the Town and Country Planning Act, which imposes a four-year time limit for taking enforcement action against breaches of planning control.

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