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Law enforcement agencies across the UK successfully lobbied to use a facial recognition system acknowledged as discriminatory against women, young people, and members of ethnic minority groups, after complaining that a less biased version generated fewer investigative leads.

How the System Works

British police utilize the police national database (PND) to conduct searches using historical face recognition. This process entails comparing a reference photograph of a suspect against a repository of more than 19 million custody photos to find potential matches.

Acknowledged Discrimination

The UK interior ministry conceded last week that the system was flawed. This admission followed a review by the National Physical Laboratory (NPL) determined it misidentified Black and Asian people and females at significantly higher rates than Caucasian males. The Home Office stated it “had acted on the findings”.

“It prompts the question of whether facial recognition only becomes useful if users tolerate discrimination in race and gender. Convenience is a poor argument for overriding basic freedoms.”

Known Issue

Internal documents reveal that this bias has been known about for over twelve months. Furthermore, police forces lobbied to reverse an initial decision that was intended to address the problem.

Police bosses were informed of the system's bias in late 2024. The Home Office-commissioned NPL review found the system was had a higher probability to produce false positives for images depicting females, individuals of Black ethnicity, and those under 40 years old.

A Policy U-Turn

In response, the National Police Chiefs’ Council (NPCC) mandated that the accuracy setting required for possible hits be increased to a point where the disparity was greatly diminished.

However, this directive was overturned the following month after forces complained that the adjusted system was generating a lower number of “investigative leads”. Internal records indicate the stricter setting reduced the proportion of searches resulting in potential matches from 56% to a just 14%.

Severe Disparities

Although the authorities refused to say what setting is now in operation, the latest NPL study found the system could produce incorrect matches for Black women nearly a hundred times more often than for Caucasian women at certain settings.

The ministry stated on these findings: “The testing identified that in a specific scenarios the software is has a greater tendency to incorrectly include some population segments in its search results.”

Operational Effectiveness vs. Bias

Describing the effect of the brief increase to the system's accuracy setting, the police records state: “The change greatly lessens the effect of discrimination across protected characteristics of ethnicity, age and sex but had a significant negative impact on police efficiency”. The papers add that police units complained that “a once effective tactic returned outcomes of limited benefit”.

Broader Rollout Plans

Meanwhile, the government has launched a two-and-a-half-month consultation on its proposals to expand the use of facial recognition technology. Policing minister Sarah Jones has labeled the tool as the “biggest breakthrough since DNA matching”.

Criticism from Advisors and Monitors

The chair of a police oversight board, head of the advisory panel for the police race action plan, commented: “We observed scant discussion in equality strategy sessions of the facial recognition rollout despite obvious cross-over with the plan’s concerns.

“This disclosure demonstrate yet again that the anti-racism commitments policing has made through the race action plan are not being translated into broader operations. Independent assessments have cautioned that new technologies are being implemented in a context where ethnic inequalities, inadequate oversight and faulty information gathering continue to exist.

“Any use of this technology must adhere to strict national standards, be subject to external review, and prove it reduces rather than exacerbates racial disparity.”

Home Office Response

A government representative stated: “We takes the conclusions of the study seriously and we have already taken action. A new algorithm has been independently tested and procured, which has demonstrated no measurable discrimination. It will be trialled early next year and will be subject to evaluation.

“The foremost aim is protecting the public. This gamechanging technology will assist officers to apprehend and prosecute offenders. There is officer review in each stage of the procedure and no further action would be pursued without specialist personnel meticulously examining the results.”