Thoburn v Sunderland City Council 2002 – Perhaps Sir John's most famous decision, and extremely controversial in the public law sphere.

The foundation of his decision was on four propositions:[5] R v Somerset County Council, ex parte Fewings – Sir John sat in the first instance hearing of this historic case, concerning the legality of a decision made to prohibit hunting on a small area of land which the council had acquired and was argued to maintain under s120(1)(b) Local Government Act 1972.

McFarlane v Relate Avon Ltd – Sir John attracted considerable press attention for stating "The promulgation of law for the protection of a position held purely on religious grounds [...] is irrational, as preferring the subjective over the objective.

This was in response to a witness statement submitted by former Archbishop of Canterbury Lord Carey that Christians should be afforded special protections under equality legislation on the grounds of earnestly held religious belief.

These statements are certainly controversial and have been fiercely contested by academics such as John Griffith and Martin Loughlin, both professors at the London School of Economics.

The essential arguments made by these authors are to the effect that the metaphysical principles that Sir John cites are highly contentious.

[8] On 5 April 2020, he died in Chelsea and Westminster Hospital, where he was originally being treated for sepsis and other conditions, due to health complications from COVID-19.