U.K. Rulings on Tax Assessments and Penalties Raise More Questions

Who bears the burden of proof when a taxpayer challenges a tax authority’s decision, and a penalty arising from the decision?

Liesl Fichardt, who heads up the International Tax Disputes and Tax Arbitration team at Quinn Emanuel, joined forces with London associates Emily Au and Julius Berling to address that question in Tax Journal. Readers will learn:

• The new arguments available to taxpayers following the UK Court of Appeal’s judgment in HMRC v. Sintra Global Inc [2025] EWCA Civ 1661. The court held that the tax authority, HM Revenue & Customs, must prove the tailored penal elements, while the taxpayer bears the burden of disproving the underlying assessment.
• How the First-tier Tribunal’s decision in J Hall v HMRC [2026] UKFTT 124 (TC) fits in the picture, how protections afforded by Article 6 of the European Convention on Human Rights come into play, and how various “quasi-penalty” regimes could similarly benefit from Article 6 protection.  
• Why the line between the bespoke elements and the underlying tax liability is likely to spur future litigation.

Fichardt, Au and Berling offer detailed analysis of this evolving area of U.K. tax law as well as practical notes for practitioners.

Read the full Tax Journal here (free registration): Sintra, Hall and the reshaping of HMRC’s burden of proof