SIR, The Shadow Chancellor Ed Balls recently pledged to invest in the NHS by implementing a mansion and tobacco tax. At the same time Labour has pledged not to increase national insurance or VAT. That means that a central pillar of Labour's election campaign is founded on the credibility of the mansion and tobacco tax. On the surface, both policies appear to make sense. The Institute of Fiscal Studies said that a mansion tax "could" raise £1.7 billion a year. At the same time the Labour Party believes that a tax on tobacco "would" raise £150 million a year based on the outcomes of a similar policy in the United States. But a closer look reveals that Labour's pledge is not only economically irrational, but unethical. Firstly, the public ought to be aware that cigarettes are already taxed at 86 per cent of the price of a pack. At the same time the number of smokers has been reducing which means that the revenue stream and therefore taxable income is not concrete. We quite rightly want people to stop smoking, however, this policy depends on people continuing to smoke. That is simply odd. Secondly, the mansion tax does not factor in the costs of administrating the policy which means a larger state, and another level of complexity. It also ignores the losses of stamp duty and the unintended consequences of taxing people who have worked hard for their home, however, do not have a reliable revenue stream. How the British homeowners and investors would respond is unclear. The bottom line is this. The NHS will require a specific amount of investment to be maintained, and to keep up with the level of inflation which is higher than national inflation. The incomes stream from a tobacco and mansion tax are 'possibilities' and depend on the behaviour of smokers and investors and savers. We all want a successful and efficient NHS. However, it is important that the next government only pledges what it can deliver.This tells us a lot about the standard of the opposition in the General Election. And whether we want them governing nationally. Mat Davies (Monmouth)