Cheerleaders for new taxes are often in short supply. So the UK government may be congratulating itself on plaudits from its own side for the 45 per cent top rate of income tax announced on Monday. But the income tax changes laid out this week deserve opposition not applause. They lack simplicity and effectiveness, and exacerbate distortions in the tax system.

The new regime is too complex. The two-step restriction of the tax-free personal allowance from 2010-11 leading to its abolition for those on or above about £146,500 ($225,840) creates two narrow bands where the marginal tax rate spikes at 60 per cent. Separately, 2011-12 will see the new top rate on incomes of £150,000 or more.