Speed Read: HMRC's current approach of issuing discovery assessments in order to 'protect their position'. This is likely to create a great deal of uncertainty for many taxpayers and, in some cases, appears to run contrary to recent case law (including Corbally-Stourton, Hankinson and Smith) which has introduced a 'more likely than not' test as to whether or not HMRC has discovered an insufficiency to justify raising a discover assessment. Any taxpayer who has recently received a discovery assessment would be well advised to consider its validity in light of this case law.