[2025] UKUT 009 (AAC)

For the reasons I have given I conclude that the Tribunal was labouring under a mistake of fact amounting to an error of law.

It is not clear what the Tribunal would have decided had it not been labouring under any mistake of fact. The error cannot, therefore, be said to be immaterial. The interests of justice require me to set aside the decision of the Tribunal to give JB an opportunity to have his detention reviewed effectively.

This requires all the statutory criteria to detention to be assessed afresh. This will involve hearing evidence and making findings of fact. The First-tier Tribunal, with its expert members, is best placed to carry out this task.

I note that JB disputes many of the findings of fact made by the Tribunal, but because the panel hearing the remitted appeal will not be bound by the FtT Decision and will consider all matters afresh, any errors that the Tribunal may have made in its assessment of the evidence and its findings of fact will be overtaken by the new panel’s decision-making.

Ms Kelly has invited me to comment on the Tribunal’s approach to fact finding. I do not consider it appropriate for me to do so given that the new panel will be deciding matters afresh, other than to say that findings of fact must be made based on evidence rather than mere assertion, and to endorse the approach set out by the Upper Tribunal in AM v Partnerships in Care Ltd [2015] UKUT 659 (AAC) and by the High Court in R (AN) v MHRT [2005] EWHC 587 (Admin).

I allow the appeal and set aside the decision under section 12(2)(a) of the Tribunals, Courts and Enforcement Act 2007.

The case must (under section 12(2)(b)(i)) be remitted for re-hearing by a new tribunal.