Effectiveness
It is hard to judge the effectiveness of the legislation, since as of 2010 the UK Inland Revenue have not published any figures. On 6 Jan 2004 Dawn Primarolo was asked in Parliament how many investigations under the IR35 regulation have (a) been initiated, (b) resulted in additional revenue and (c) been concluded without securing additional revenue. In a written answer she replied that it was not possible with any accuracy to isolate data relating solely to this legislation.
On 15 June 2009 in the House of Commons Labour MP Terry Rooney (Bradford North) asked the Chancellor of the Exchequer "how many investigations concerning IR35 were launched in each of the last five years; and how many of them resulted in (a) prosecution, (b) an increase in tax due and (c) no further action". Kitty Ussher speaking for the Chancellor replied, "The intermediaries legislation, commonly known as "IR35", was introduced with effect from 6 April 2000 to counter the avoidance of employed levels of tax and national insurance by individuals providing their services through intermediaries. Disclosure of HM Revenue and Customs' compliance data relating to the legislation would result in a risk of non- compliance with the legislation. Accordingly I am not able to provide the data requested." The July 2009 issue of IT Now, the British Computer Society magazine, reported that between April 2002 and March 2008 the Government had raised £9.2 million under IR35 legislation compared to the £220 million that it was initially expected.
The Professional Contractors Group (PCG) claims 1462 wins to 6 losses in appeals for IR35 and S660A together, however this only applies to its own members and may not be typical of the wider picture.
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