How should HMRC treat taxpayers who are substantially in the same position but procedurally in different stages of resolving their affairs with HMRC, when it changes its mind about the correct view of the law? After Mansworth v Jelley in 2003, the Revenue’s web guidance allowed many claims for capital losses. Six years later, it changed its mind, even though some cases were still unresolved. HMRC applied the revised view of the law. Mr Hely-Hutchinson applied for judicial review, as he had been given a legitimate expectation as to how he would be dealt with. Although he could show no detrimental reliance, he claimed that to treat him differently from those already settled purely because of procedural reasons was ‘conspicuously unfair’. Whipple J agreed but the Court of Appeal disagrees. Should not ‘fairness’ be an issue of substance?