The causes which resulted in occupiers of lands and buildings (and not the owners thereof) being assessed to local rates and to the adoption of the net annual value of property occupied as the basis or standard of assessment, to the exclusion of any other basis, are stated in Pro fessor Cannan's History of Local Rates. That basis has, however, been modified from time to time in cases where, by reference to the two canons of (i.) the ability of the ratepayer to pay and (ii.) the benefit derived by him from rate expenditure, the strict appli cation of the basis of net annual value seemed likely to lead or had led to injustice. Thus, for the purposes of the Lighting and Watching Act of 1833—an Act which enabled parish authorities to undertake the lighting of streets and the provision of fire en gines—it was deemed unjust to rate the occupiers of agricultural land on the same basis as the occupiers of dwelling-houses, and therefore Parliament (in effect) provided that, while the last men tioned occupiers should pay in proportion to the whole of the net annual value of the dwelling-houses, occupiers of agricultural land should pay in proportion to one-third (now one-quarter) only of the net annual value thereof. A similar plan was adopted in the case of the Public Health Act of 1848 (and is now embodied in the Public Health Act of 1875) under which, while the occupiers of dwelling-houses and similar properties contribute to rates for sanitary expenses in proportion to the whole of the net annual value of the property in their occupation, certain occupiers (e.g.,
occupiers of agricultural land and land used as a railway or canal), who are deemed to derive but little advantage from sanitary ex penditure, contribute (in effect) to that expenditure in proportion to one-quarter only of the net annual value of the land. The same plan was applied to certain rates (e.g., rates for the relief of the poor, education and rural highways) in the Agricultural Rates Acts of 1896 and 1923 and the Rating and Valuation Act of 1925, with the result that occupiers of agricultural land have been liable to contribute, in respect of that land, to those rates in proportion to one-quarter only of the net annual value of the land.
The abatements made under the above-mentioned Acts of 1896 and 1923 were in respect of long-established rates, and conse quently, if those abatements had stood alone, they could not have been made without increasing immediately the amount of rates payable by other classes of ratepayers; and with a view of miti gating (in 1896) or avoiding (in 1923) such an increase, grants in respect of the abatements were made from national taxation.