Clifford James successfully acted for the Appellant in Lex Autolease Limited v PZU SA Powszechny Zaklad Ubezpieczen  and Lex Autolease Limited v Euro Packaging Limited . The cases clarified an important issue relating to a Claimant being able to rely on expert evidence in diminution cases. His Honour Judge Platt ruled in favour of Appellant in both appeals, ruling:
- The test for considering expert evidence is to assess whether the expert evidence is ‘reasonably required’.
- Expert evidence is reasonably required in diminution cases pursuant to Payton v. Brooks (1974).
- Refusing permission on grounds of proportionality is wrong in law.
Stewart Fairhurst commented “There have been growing number of challenges relating to a Claimant being granted permission to rely on expert evidence in diminution cases. This reasoned judgement from a very experienced Judge provides clarity to Parties engaged in diminution litigation.”