The phrase "Daylight Robbery" is often used to describe unfair trading practices or extortionate prices – and so blatantly that it takes place in the cold light of day. But it is said to originate back to the late 17th century, and the introduction of an unpopular tax by King William III in the 1690s.
In order to raise much-needed funds, William III introduced the window tax, which targeted wealthy homeowners who had larger houses, and by extension, more windows. When it was introduced, homes with up to ten windows paid a flat rate of tax, while those with between 10 and 20 windows paid about twice the flat rate, and those with more than 20 windows paid about three times the flat rate of tax.
About 100 years after it was introduced, the tax levy was tripled by Prime Minister William Pitt the Younger, to raise funds to help cover the spiralling costs of the Napoleonic Wars, which only backfired as it resulted in thousands of windows being bricked or boarded up, much of which is still visible today. The tax was, unsurprisingly, hugely unpopular, principally because it was deemed by many as a tax on the elements of light and air. The Window Tax was repealed in 1851, though the remnants of bricked up windows can still be seen in buildings across London.