The inherent jurisdiction of the Irish High Court: Interface with psychiatry.

The term "inherent jurisdiction" refers to a set of default powers, usually not set out in statute, which enables a court to fulfil its roles. We discuss recently reported cases where such power has been exercised by the Irish High Court and what this means for psychiatrists in practice. These cases demonstrate that (a) the Irish High Court can be involved in decision-making where there is a lacuna in mental health legislation and a lack of mental capacity; (b) when a minor has been placed by the Court in a specialist facility in the UK and then attains the age of 18 years, decisions can be based on mental capacity but not on preventative detention on the basis of risk; (c) complexities arise when definitions of mental disorder vary between jurisdictions, especially when the Court orders involuntary detention in a case where statute would not ordinarily allow this; and (d) the appropriate route to seek decision-making for adults with mental incapacity is through Ireland's "Ward of Court" process, although, on the face of it, this seems to be contrary to the approach taken in other cases in which inherent jurisdiction was used. Overall, while it is reassuring for state health services that they can seek to approach higher courts in respect of decision-making in complex cases, some of these decisions raise important ethical questions for psychiatrists who may be asked to treat patients detained under their care who may not have a treatable mental illness as their condition falls outside of mental disorder within Irish legislation. We recommend that clear guidance is made available to psychiatrists in light of these judgments, particularly as there is likely to be a reconsideration of cases where Irish patients are placed in the UK given the UK's planned departure from the EU.