Why is tax avoidance a reason for letting people off tax?

Tax dodging, the Laffer curve, and the 50p rate

The reason given for cutting the 50p rate of tax to 45p was avoidance. It wasn't clearly phrased as such – most of the talk was about how it had raised less money than expected, or had changed behaviour in ways that harmed growth – but that is what it was nonetheless. To many, this will seem strange. "You avoided tax, so we will make you pay less". But it is an integral part of the line of thought that lies behind the cut.

Art Laffer first made the argument that cutting tax rates could boost revenue. The reasoning is broadly that, when the marginal tax rate (the amount you pay on each extra pound earned) gets too high, people start doing things to reduce their taxable income.

The palatable version is that they work less, because an extra hour of work no longer pays as well as it did, and this is probably true; there are certainly anecdotal tales of highly paid consultants turning down work later on in the year to spend more time at home.

The less palatable version is that they avoid more tax, because spending the money and effort required to set up a limited company, be paid "overseas", or funnel your income through a Swiss bank account in the name of your dog becomes more worthwhile the more it saves you.

Both of these "behavioural changes" are factored in to the Laffer curve, the rough prediction of how much revenue will be gained at various marginal tax rates. HMRC produced three such curves, each based around a different "taxable income elasticity" (TIE), a measure of how much an individual's behaviour changes given the tax rate:

They based their analysis around a TIE of 0.45 (a figure basically plucked from thin air – HMRC admit the evidence to choose is "extremely limited", and the studies they cite range from -0.6 to 2.75), which showed a peak of revenue at around 48 per cent. Quite why this then led the Chancellor to cut the rate to three per cent below that is unclear. If he wanted to raise revenue, his own analysis is showing that he's done it wrong.

The problem is, one thing which affects the TIE is the ease with which one can avoid tax. Make tax avoidance harder, TIE goes up, and the peak revenue rate increases. In fact, given the anti-avoidance measures announced at the budget yesterday, TIE will already be higher than it was at the time of the analysis, boosting the argument for keeping the 50p rate.

There is one massive category of avoidance which can't be cited as a reason for cutting the rate, however. The HMRC's stats show that £6.6bn less income was declared in 2010-11 due to it being "forestalled" – paid the year before, so as to take advantage of the lower rate. This is avoidance on a massive scale (Richard Murphy points out that it is £1.6bn more than the estimation for all tax avoidance in 2011), yet, contra Tim Worstall, it has no bearing on the decision on whether or not to cut the rate, because it can only ever be done once. 

By cutting the tax so early in its life, Osborne has ensured that we make the decision unable to know the full effect of cutting it. We can guess at how much will have been raised for the 2011-12 tax year, when forestalling was harder (although not impossible, and HMRC warn that it "continues to reduce revenues in 2011-12 and beyond"), but by the time we know for sure, it will be too late. The 45p tax will be in, and there won't be a "normal" year of the 50p rate to compare it to.

Tax dodging is an emotive issue. Credit: Getty

Alex Hern is a technology reporter for the Guardian. He was formerly staff writer at the New Statesman. You should follow Alex on Twitter.

Getty Images.
Show Hide image

Jeremy Corbyn challenged by Labour MPs to sack Ken Livingstone from defence review

Former mayor of London criticised at PLP meeting over comments on 7 July bombings. 

After Jeremy Corbyn's decision to give Labour MPs a free vote over air strikes in Syria, tonight's Parliamentary Labour Party (PLP) meeting was less fractious than it could have been. But one grandee was still moved to declare that the "ferocity" of the attacks on the leader made it the most "uplifting" he had attended.

Margaret Beckett, the former foreign secretary, told the meeting: "We cannot unite the party if the leader's office is determined to divide us." Several MPs said afterwards that many of those who shared Corbyn's opposition to air strikes believed he had mishandled the process by appealing to MPs over the heads of the shadow cabinet and then to members. David Winnick declared that those who favoured military action faced a "shakedown" and deselection by Momentum activists. "It is completely unacceptable. They are a party within a party," he said of the Corbyn-aligned group. The "huge applause" for Hilary Benn, who favours intervention, far outweighed that for the leader, I'm told. 

There was also loud agreement when Jack Dromey condemned Ken Livingstone for blaming Tony Blair's invasion of Iraq for the 7 July 2005 bombings. Along with Angela Smith MP, Dromey demanded that Livingstone be sacked as the co-chair of Labour's defence review. Significantly, Benn said aftewards that he agreed with every word Dromey had said. Corbyn's office has previously said that it is up to the NEC, not the leader, whether the former London mayor holds the position. In reference to 7 July, an aide repeated Corbyn's statement that he preferred to "remember the brilliant words Ken used after 7/7". 

As on previous occasions, MPs complained that the leader failed to answer the questions that were put to him. A shadow minister told me that he "dodged" one on whether he believed the UK should end air strikes against Isis in Iraq. In reference to Syria, a Corbyn aide said afterwards that "There was significant support for the leader. There was a wide debate, with people speaking on both sides of the arguments." After David Cameron's decision to call a vote on air strikes for Wednesday, leaving only a day for debate, the number of Labour MPs backing intervention is likely to fall. One shadow minister told me that as few as 40-50 may back the government, though most expect the total to be closer to the original figure of 99. 

At the end of another remarkable day in Labour's history, a Corbyn aide concluded: "It was always going to be a bumpy ride when you have a leader who was elected by a large number outside parliament but whose support in the PLP is quite limited. There are a small number who find it hard to come to terms with that result."

George Eaton is political editor of the New Statesman.