DD v Durham County Council & anor  EWCA Civ 96 (Sir John Thomas (President), Moore-Bick LJ, Rimer LJ): This appeal was against the refusal of the appellant’s application for permission to bring a claim against the local authorities under s 139(2) of the Mental Health Act 1983 (“the MHA 1983”) as a result of the failure of two approved mental health professionals (AMHP) to discharge their statutory duties. The appellant had been convicted of assault and sentenced to a two year extended sentence of imprisonment. His detention in prison was extended following an attack on a psychiatrist. An AMHP made an application for his detention for assessment under section 2 MHA 1983 at the Hutton unit. He was admitted and detained at this unit. At the end of the period for assessment a new assessment was conducted by a different AMHP on behalf of the respondents. The second AMHP concluded that the appellant should remain detained at the Hutton Unit under section 3 of the MHA 1983. The appellant claimed that the Hutton Unit practised a regime which was not suitable for him, given his mental condition. It was accepted that for the purposes of his application under s.139 of the MHA 1983 the conditions in the Hutton Unit amounted to an arguable breach of his rights under the ECHR. On allowing an appeal the court held the scope of the duty of an AMHP was a question of law of some importance. The only point that the court could consider was whether the judge was correct in refusing leave. The threshold under s 139 MHA 1983 was a low one and there was no doubt that the appellant’s argument met that threshold. It was at least arguable from St George's Healthcare NHS Trust v S  3 W.L.R. 936 that there was a duty of the kind suggested on an AMHP. Further the AMHP had a duty to satisfy himself that it was appropriate for the patient to be detained and it must be arguable that the duty extended at least to bringing a degree of independent judgment to bear on the recommendation as to the hospital and regime made by the medical practitioners. (click here for judgment).