Considered by the Ombudsman, Marie Anderson, to be an area of high risk where failings could lead to injury or death, the wide-ranging investigation will consider the existing PSNI service instruction that relates to police interacting with those who have a vulnerability.

It will include the ‘duty of care’ of police officers as reflected in a regional interagency protocol, which provides a framework for cooperation and joint working between the PSNI, Northern Ireland Ambulance Trust and Health and Social Care Trusts.

The aim of the protocol is to ensure that people with a mental disorder are managed in a safe, efficient and effective manner when agencies and professional staff are discharging their duties under the Mental Health (NI) Order 1986.

The operation of the protocol is an area that has been highlighted in an ‘own motion’ investigation undertaken by the Ombudsman and was one of the main factors that informed her decision to conduct a ‘policy and practice’ investigation.

Mrs Anderson said: “This own motion investigation, together with other cases being investigated by my office, highlighted issues around how the regional interagency protocol operates in practice and the inherent risks, both for the vulnerable person and the police officers concerned.

“The rules and ethical standards that apply to police in this area are complex and the protocol is a detailed document, where there is a degree of discretion for police officers.

“My concern centres on how training, guidance and the application of the regional interagency protocol itself are translated into the daily operational policing environment in supporting people who have vulnerabilities, whether as a result of age, mental ill-health, addictions or homelessness.”

She added: “I anticipate that there are important lessons to be learned for PSNI by a policy and practice investigation that draws on the issues which have emerged from casework in my office.

“It is my aim that the outcome will help inform future PSNI policies and provide clarity on police officers’ responsibilities in this area.”

The Police Ombudsman said it expects to report on the outcome of the investigation in “the late autumn of 2023”.