GEORGE OSBORNE sees himself as a reformer. The chancellor promised that, unlike his Labour predecessors, he would take tough decisions to improve the economy, whether this was liberalising planning to boost housebuilding, promoting competition between energy firms, or cutting red tape for businesses. When in opposition, Mr Osborne also set his sights on the tax code. In 2008 he proclaimed (with some hyperbole) that Britain’s code was “the longest [and] probably the most complex in the world”, promising “long-term thinking on simplification” if he got into power. He even mulled the idea of a flat income tax, where everyone pays the same rate regardless of their earnings.

Yet eight years on, the tax system looks as fiddly as ever. In 2010 Mr Osborne set up an Office of Tax Simplification (OTS) to hold the government to account, rather as the Office for Budget Responsibility (OBR) acts as a watchdog over fiscal policy. The OTS identified 1,042 tax reliefs in Britain. Plenty were ripe for reform. People could even get relief for the first 15p of “luncheon vouchers”, an idea dating from a time of rationing in 1946.

Relief on luncheon vouchers is no more, but other wheezes have proliferated. In 2012 oil firms charged with decommissioning old rigs were given relief on corporation tax. A year later Mr Osborne allowed workers to cede employment rights, such as the ability to claim unfair dismissal, in exchange for tax-free shares in their firms. From March children under 16 will not have to pay air-passenger duty (only in economy class, mind). By March 2015, the OTS found, the number of reliefs had risen to 1,156. From 2009 to 2015 the number of pages in the tax code grew by about a third.

Not all tax reliefs are foolish or damaging. The largest, costing roughly £80 billion ($115 billion) a year, is the personal allowance for income tax, a simple and progressive policy whereby people pay no tax at all on the first £10,600 of their earnings. So Adam Corlett of the Resolution Foundation, a think-tank, tries to capture the underlying complexity by adopting a restrictive definition of tax reliefs, which covers measures designed to “promote economic and social objectives”. Such reliefs resemble public spending. The state could, for example, give selected small firms either a grant or a tax break; the effect on the recipient (and on taxpayers) is practically identical. By this measure, the cost of tax reliefs rose in 2010-15 from 5.5% to 6% of GDP.

All this has made life no easier for business. A report on the coalition government’s tax policies from Oxford University’s Centre for Business Taxation found “little evidence of real simplification”. According to the World Bank, since 2010 the time taken by the average firm to pay corporate, value-added and labour taxes has remained unchanged, at 110 hours a year (though, happily, this remains relatively low by international standards).

On top of this, a failure to eliminate or simplify tax reliefs also hits the public finances. They encourage tax avoidance, which official estimates put at around £3 billion a year. And in a world of tight budgets, with spending by departments under ruthless scrutiny, many seem to offer poor value for money. Tax reliefs for film-makers, for example, whereby a production company can claim a rebate of 25% of film-production spending, has boosted the number of British flicks (“Last year alone we saw eight British-made films nominated for an Oscar,” Mr Osborne enthused in 2015). But it is not clear that this is worth the £2 billion cost to the government over the period from 2007 to 2015.

Meanwhile, relief on capital-gains tax for entrepreneurs costs £3 billion a year, three times more than official forecasts predicted. Yet a report commissioned by the tax office found “few cases where [it] appeared to have a major influence on the business behaviour and tax planning of claimants”. At £100 billion a year, according to Mr Corlett’s calculation, revenue forgone in tax reliefs is roughly equal to the NHS budget; but few have been assessed to see whether they are worth the cost.

The first year of a new parliament is when big decisions on tax are best made. Mr Osborne will have to announce some in next month’s budget, not least because the fiscal outlook has deteriorated since his autumn statement in November. The Bank of England has cut its forecast of GDP growth in 2016 to 2.2%. The Institute for Fiscal Studies (IFS), a think-tank, reckons that receipts from income tax and national insurance in 2020 may be £5 billion lower than expected in November. So Mr Osborne will be looking for ways to make up the shortfall. He could choose a 33% flat rate on pension tax relief, yielding about £5 billion a year, according to Capital Economics, a consultancy. A more modest possibility is cutting tax relief on claims for travel expenses, which would yield £300m.

Such reforms could even make the tax system a mite simpler. But the direction of travel is, as ever, towards greater complexity. The Treasury has never published an overall strategy for the tax system, complains Paul Johnson of the IFS. Instead, chancellors pick tax policies for reasons of political expediency. In July Mr Osborne raised the threshold for inheritance tax from £650,000 for a couple to £1m. The increase applied only to housing wealth, not financial assets. The effect is perverse, encouraging people to funnel yet more cash into Britain’s bubbly housing market.

The OTS might have acted as a check on such wheezes. But it has little power. Unlike the OBR, few people have heard of it. It has had a small budget and has not been sufficiently independent of government, argues Julian McCrae of the Institute for Government, a think-tank. The Treasury fiercely guards its tax prerogatives. So far the OTS has not even been involved in pre-budget discussions about new tax measures, says Tracey Bowler of the IFS.

In an ideal world the Treasury would ditch its long-standing practice of keeping policies under wraps until the chancellor presents them in his annual budget, argues Mr McCrae. Consulting in advance would encourage officials to consider fully the impact of proposed changes, thus dissuading economically damaging political grandstanding. It is getting better at this, consulting on changes to corporate taxation, for instance. But that is tinkering around the edges. Unless Mr Osborne changes course and revives the idea of simplification, the unfortunate reality is that the tax system is likely only to become more byzantine.