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The Manchester Arena Inquiry has now concluded. The closure notice from the Inquiry Chairman is available here.

Volume Three: Radicalisation and Preventability
Volume Three: Radicalisation and Preventability (20pt version)

Part 24 Preventing the Attack

Key findings

  • There was a significant missed opportunity to take action that might have prevented the Attack. It is not possible to reach any conclusion on the balance of probabilities or to any other evidential standard as to whether the Attack would have been prevented. However, there was a realistic possibility that actionable intelligence could have been obtained which might have led to actions preventing the Attack.
  • The reasons for this significant missed opportunity included a failure by a Security Service officer to act swiftly enough.
  • The Inquiry has also identified problems with the sharing of information between the Security Service and Counter Terrorism Policing, although none of these problems is likely to have had any causative significance.


For the reasons set out in my determinations of 13th September 2019 and 25th October 2021,1 a significant amount of the material that was relevant to the question of whether the Attack could have been prevented by the Security Service or Counter Terrorism Policing was the subject of a Restriction Order under section 19 of the Inquiries Act 2005. The basis of the Restriction Order was national security. As a result, the majority of the evidence which forms the basis of this Part of Volume 3 was given during a closed evidence hearing.

Having heard all of the evidence, I am satisfied that a closed evidence hearing was necessary and that a closed part of my Report is justified. Hence, Volume 3 of my Report will be in two parts: Volume 3 (open) and Volume 3 (closed). However, the fact that part of Volume 3 must be closed does not mean that more cannot be known by members of the public than is currently the case. As I have said throughout my investigation, I am committed to placing as much information in the public domain as can be done safely. What follows in this Part of Volume 3 (open) is a gist of my conclusions on the evidence I heard in the closed evidence hearing. Also addressed in this Part is the relevant evidence from the open hearing on the issue of preventability.

As part of my ongoing commitment to make public as much information as I can, some of the closed evidence has already been the subject of a gist.2 That evidential gist is dated 7th February 2022. It was read into the Inquiry record on 15th February 2022.3 This is available on the Inquiry’s website. As I have now reached findings on the evidence, it is possible for me to place a greater amount of information into the public domain.