top of page

School of Human Sciences

Institute of Lifecourse Development

University of Greenwich

London SE10 9LS

Twitter: @GRecognisers

Searching for Thames Valley Police Super-Recognisers

Professor Josh P Davis

It is good to see Professional Security Magazine cover the first testing sessions of UK police for a number of years to see if any possess super-recognition ability, held on 25 November 2020. Organised by partners Super-Recognisers International and the Association of Super-Recognisers, a few members of Thames Valley Police completed 12 tests in online and monitored examination conditions.

The tests measured their short-term face memory, long-term face memory, simultaneous face matching, and ability to spot faces in a crowd (see Davis, 2019; 2020). The examination sessions were conducted as a component of a three-day training course. To determine if any of the attendees were super-recognisers, their scores on each test were compared to large groups of super-recognisers who had piloted the tests previously. These were used to generate “z-scores” in which a z-score of zero is equal to the mean (average) of the group of pilot super-recognisers. A z-score of +1 is equal to 1 standard deviation above the super-recogniser mean.

There were one or two exceptionally high scorers, quite surprising to find in such a small group of officers, as only approximately 2% of the population would be expected to achieve criteria on each component alone. It should be noted that the z-scores reported in the article have been summed across the four different test types. To calculate the overall combined mean of each participant, the score should be divided by four. The highest score is still highly impressive.


Davis, J. P. (2021). CCTV and the super-recognisers. In C. Stott, B. Bradford, M. Radburn, and L. Savigar-Shaw (Eds.), Making an Impact on Policing and Crime: Psychological Research, Policy and Practice (pp 34-67). London: Routledge. ISBN 9780815353577:

(free to download pre-print here:

(free to download pre-print here:


Recent Posts

See All


bottom of page