Operation Coniston: Enhancing stop and search with supervisor reviews of Body Worn Video

Met officers routinely use Body Worn Video (BWV) equipment to capture video and audio when conducting a stop and search (S&S).

In response to recommendations from the Independent Office for Police Conduct (IOPC) and as part of ongoing efforts to improve S&S, the Met’s Strategic Insights Unit (SIU) conducted a trial to examine the impact of monthly supervisor-led reviews of BWV footage of S&S encounters. Specifically, they wanted to understand the impact of regular reviews on:

• Volume of searches conducted
• Search outcome
• Quality of the encounter
• Officers’ views of the process

Method

This was a large randomised controlled trial (RCT), involving 194,989 stop and searches from 12,136 officers reviewed between August 2021 and January 2023.

During the reviews, supervisors were instructed to watch the BWV footage with the searching officer, and to discuss the quality of the search using the supervisor’s question template which reflects the Met's guidance for best practise on how to conduct a stop and search. Supervisors’ assessments were documented and submitted via questionnaire.

Findings

• Volume of searches conducted: BWV review did not impact the volume of searches conducted, indicating that the reviews did not reduce officers’ willingness to conduct searches.
• Search outcome: Where BWV footage was reviewed, searches were slightly (and statistically significantly) more likely to lead to criminality detection, suggesting that officers who conducted reviews may have targeted their searches more effectively.
• Quality of encounter: Several aspects of the officers’ behaviour (as assessed by their supervisor) improved after repeated reviews, though, without knowing what happened in searches conducted by officers who weren’t reviewed, it’s impossible to know for certain whether the changes resulted from the reviews or other factors.
  
  • Officers improved on:
    • introducing themselves
    • explaining the search procedure
    • ensuring the co-operation of searched persons
    • acknowledging the encounter by handing over the relevant receipts
  • Officers were less effective, however, in ensuring a positive departure
• Views of the process: Officers and supervisors had mixed views on the intervention, with both being concerned about the additional workload the reviews introduced.

Building on the results from this pilot, the Met is developing a new business-as-usual system for reviewing BWV footage of stop and search, streamlining the review process and taking a data-driven approach to implementation.

This report was prepared by the Met’s Strategic Insight Unit.

The report was reviewed by two members of the independent Police Science Council and the NPCC Chief Scientific Adviser.