There is however nothing new in this business of allowing MPs favourable status in the decision as to which is their main residence & which their second home is not new. The legislation for the Poll Tax of 1988 stated (Section 2) that
A person is subject to a charging authority’s personal community charge on any day if … (b) he has his sole or main residence in the area of the authority at any time on the day
If it was not the main residence then the (usually much higher) standard community charge applied. (Section 3)
This was one of the attempts by government to deal with the hated second homes, which most people assume belong solely to rich townies buying holiday homes in rural areas & pricing the locals out of the market
In order to stop people from dodging the higher rate, the local authority could decide whether the dwelling was or was not your main residence, using criteria such as where you kept your books
This was particularly hard on those who worked in London during the week but had their main home elsewhere. They had to pay the high Standard Charge in London, even for a bedsit in a broom cupboard, on top of an amount on a modest provincial home which was (usually) much higher than that paid by Kensington millionaires
One of the principle aims of the poll tax was to reduce the (perceived) burden of rates on Londoners, which was achieved by reducing the subsidy paid to other areas. The result was that poll tax was very low in London but that the increases were swingeing in many areas, such as the North of England, thus mutliplying up the bill beyond the level that would have come from paying per caput rather than just per household
But guess what – MPs were given a special exemption from the payment of the standard charge