Inquests following investigations by an Accident Investigation Branch Decisions in Norfolk and West Sussex

The type of inquest required for deaths investigated by an Accident Investigation Branch (AIB) has changed significantly following decisions in R (Secretary of State for Transport) v HM Senior Coroner for Norfolk [2016] (Norfolk) and HM Senior Coroner for West Sussex v Chief Constable of Sussex and Secretary of State for Transport [2022](West Sussex).

Background

The Norfolk case concerned an air crash which resulted in the deaths of four men. The Air Accident Investigation Branch (AAIB) had, by the time of the inquest, produced its final report. The specific issue was whether a Coroner could compel disclosure of protected material. It was determined by the Divisional Court that it would not be in the public interest for a Coroner to reinvestigate matters already covered by the AIB, save where there is credible evidence that the AIB’s investigation was incomplete, flawed or deficient.

The West Sussex case concerned eleven deaths in the Shoreham Air crash and, following the decision in Norfolk, the High Court gave further guidance on the correct application and interpretation of what are commonly referred to as the Norfolk principles.

Following the decisions, a Coroner conducting an inquest into a death which occurred in an accident investigated by an AIB, should not consider it necessary to investigate again the matters covered by that investigation, and it would not be in the public interest to do so.  

There should, in general, be no need to adduce any further evidence on any issue investigated by an AIB, save for limited supplementary evidence from an AIB Inspector such as is necessary for the purposes of explanation or clarification. Only if there is “credible evidence” that an AIB’s investigation was “incomplete, flawed or deficient” may a Coroner need to investigate a matter.  This is a high threshold and it is envisaged that cases where there might be an obvious deficiency will be rare.

When considering whether there is credible evidence that the investigation was incomplete, flawed or deficient, “this is intended to be a decision taken primarily on the basis of the information available to the coroner, and with due regard to the specialist expertise of the [AIB]”. A coroner “should be very slow to find credible evidence that an expert investigation was incomplete, flawed or deficient”.

The Divisional Court appears to have been concerned that if a Coroner’s inquest was to cover the same ground as the AIB investigation “very significant sums of money and other precious resources [would be] expended unnecessarily”.  There is also a risk that if the inquest were to re-investigate matters already considered by an AIB, the (non-expert) jury may reach a conflicting conclusion based on more limited evidence, damaging public confidence.

Rather, it is appropriate, as stated by the Divisional Court, that these issues are investigated by a single investigation. The Court’s conclusion was that due to an AIB’s expertise in accident investigation and the fact it has the best access to the evidence, including the opportunity to interview any witnesses confidentially and in a timely manner, the AIB is best placed to undertake that investigation.

This position was re-affirmed by R (Mid and West Wales Fire and Rescue Service v HM Acting Senior Coroner for Pembrokeshire and Carmarthenshire) [2023] (Mid and West Wales) which involved an inquest into the death of a fire fighter in a collision between two boats during a marine training exercise, and one that had been investigated by the MAIB.  The fire service sought judicial review of the Coroner’s ruling that the investigation by the MAIB was not incomplete, flawed or deficient, but this was rejected by the Divisional Court. 

The decision establishes that the relevant part of the decision in Norfolk was clearly part of the ratio of that decision and it further illustrates the high threshold that must be crossed to establish an AIB investigation is arguably incomplete, flawed or deficient.

The practical effect of the Norfolk principle

The approach is more likely to have greater impact on those industries where specialist internal expertise may not readily accept the findings of an independent investigation. If there is opportunity to challenge the evidence, methodology and/or conclusion of the AIB during the consultation period of the AIB investigation report process, then this opportunity should be taken.

The extent of the matters investigated in an inquest of the type described above is much more limited than it would previously have been. This affects the inquest hearing, and the scope of the investigation beforehand including the nature of any disclosure required.

The practical effect of the Norfolk principle is not to limit the scope, but to determine how the matters falling within scope should be determined.  Where a matter has been investigated by an AIB, it should not be necessary for the Coroner to investigate again by adducing evidence. Rather, the inquest should adopt the AIB’s findings and conclusions on the matter.  Other matters within scope but not investigated by the AIB fall to be investigated by the Coroner in the usual way.

The Coroner determines the disclosure that is required for the inquest but given the Norfolk principle, the Coroner may decide that significantly less disclosure is required concerning matters that have already been investigated by the AIB.  It would not usually be appropriate for the Coroner to direct disclosure of documents held by the AIB.  Again, if there are other matters within scope that have not been investigated by the AIB, then the Coroner should seek disclosure in the usual way.

As for witnesses, there will generally be no need to adduce further evidence on any matter that has been investigated by the AIB save from the AIB Inspector for the purposes of explanation or clarification as necessary.  No witnesses of fact should be required on any issue investigated by the AIB, with the findings and conclusions treated as the evidence at the inquest.

It is understood that the Chief Coroner is considering publishing new Guidance in respect of inquests where accidents have already been subject to an investigation by an AIB.