Siobhan Duncan

Siobhan practises across a broad range of direct and indirect tax work and is regularly instructed by solicitors, accountants, and other tax professionals in complex contentious and advisory matters.

In addition to litigation, she advises individuals, trustees, and corporates on complex tax issues, including matters with an international or cross border dimension.

Siobhan also acted in a pro bono Upper Tribunal appeal, Mark Campbell v HM Revenue and Customs [2023] UKUT 00265 (TCC), securing the first costs order in the Tax Tribunal in favour of the Access to Justice Foundation. This decision is regarded as a landmark in support of access to justice in tax litigation.

Siobhan’s advisory work includes guidance for individuals, trustees, corporates, and professional advisers.

An established tax author and commentator, Siobhan contributes regularly to LexisPSL and has been published by Bloomsbury Professional, Tolley Tax, Tolley AI+, LexisNexis and Croner-i.

Her writing addresses capital taxes, inheritance tax, intellectual property, and wider advisory issues, and is aimed at both contentious and non-contentious practitioners. She also produces practitioner focused commentary on developments in tribunal and higher court case law.

Siobhan is the author of a forthcoming book on inheritance tax with Bloomsbury Professional.

Share: