Discovery following Tooth: what should advisers do now?

The Supreme Court judgment in HMRC v Tooth brings welcome clarity about the scope of ‘deliberate inaccuracy’ and confirms that tax returns are read as a whole. However, the Supreme Court’s dismissal of the concept that staleness may invalidate discoveries is a win for HMRC, restoring the sole focus on legislative assessment time limits. The decision will change advisers’ approach to discovery appeals whilst confirming the usefulness of ‘white space’ notes on tax returns. It also illustrates the importance of contemporaneously evidencing the facts, people’s understanding of events and advice (including during tax return preparation) in case mistakes are subsequently identified.