Introduction

There is perhaps an air of uncertainty in the world of tax avoidance. For years the rules of the game were as Peter Whiteman QC described things: 'a seesaw process between the well-advised taxpayer on the one side and the Revenue and Parliament on the other'.¹ The cat-and-mouse game whereby devices are discovered by tax advisers and closed down by legislation has been a fixed part of the legal landscape. For a comparatively niche area of law tax avoidance has generated a large number of House of Lords cases.

Then HMRC changed the rules of the game. Instead of bringing in a general anti-avoidance provision HMRC has changed the economics of tax avoidance. The disclosure...