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Law enforcement agencies across the UK successfully lobbied to deploy a facial recognition system acknowledged as discriminatory against females, young people, and individuals from ethnic minority groups, following complaints that a more accurate version produced a reduced number of investigative leads.

How the System Works

UK forces utilize the national police database to conduct retrospective facial recognition searches. This process entails comparing a reference photograph of a person of interest against a repository of over 19 million custody photos to identify potential matches.

Admitted Bias

The Home Office admitted last week that the system was biased. This acknowledgment followed a review by the government's National Physical Laboratory found it misidentified Black and Asian people and females at significantly higher rates than Caucasian males. The Home Office said it “had acted on the findings”.

“It prompts the issue of whether facial recognition only becomes effective if users accept biases in ethnicity and gender. Operational ease is a poor argument for disregarding basic freedoms.”

Long-Standing Problem

Internal documents show that this discriminatory flaw has been recognized for over twelve months. Furthermore, law enforcement lobbied to reverse an earlier ruling that was intended to mitigate the problem.

Senior officers were informed of the algorithmic discrimination in late 2024. The government-ordered laboratory study found the system was more likely to suggest incorrect matches for images depicting females, Black people, and those under 40 years old.

A Reversed Decision

In reaction, the national police leadership body ordered that the confidence threshold required for possible hits be increased to a level where the disparity was significantly reduced.

However, this directive was reversed the next month after forces complained that the modified technology was producing fewer “investigative leads”. NPCC documents indicate the stricter setting cut the proportion of queries that yielded possible identifications from over half to a just 14%.

Severe Disparities

Although the Home Office and NPCC refused to say what setting is currently used, the recent NPL study discovered the system could produce incorrect matches for women of Black heritage nearly a hundred times more frequently than for white women at certain settings.

The ministry commented on these findings: “Our evaluation found that in a specific scenarios the software is has a greater tendency to incorrectly include some population segments in its match reports.”

Operational Effectiveness vs. Bias

Describing the effect of the brief increase to the system's confidence threshold, the police records state: “The change greatly lessens the effect of discrimination across legally safeguarded attributes of race, generation and sex but had a significant negative impact on police efficiency”. The documents further note that forces complained that “a once effective tactic now delivered results of questionable value”.

Broader Rollout Plans

Meanwhile, the government has opened a two-and-a-half-month consultation on its plans to expand the use of biometric scanning systems. Policing minister Sarah Jones has labeled the tool as the “biggest breakthrough since DNA matching”.

Expert and Oversight Concerns

Abimbola Johnson, chair of the advisory panel for the national policing equality strategy, said: “We observed scant discussion through equality strategy sessions of the technology deployment despite clear relevance with the strategy's goals.

“These revelations show yet again that the anti-racism commitments the police has made via the equality initiative are failing to be integrated into broader operations. Our reports have warned that innovative tools are being rolled out in a context where racial disparities, weak scrutiny and faulty information gathering already persist.

“Any use of facial recognition must meet strict national standards, be subject to external review, and demonstrate it diminishes rather than compounds ethnic bias.”

Home Office Response

A government representative said: “We treat the conclusions of the report with utmost gravity and we have already taken action. A updated software has been externally evaluated and procured, which has no statistically significant bias. It will be tested early next year and will be undergo further assessment.

“Our priority is protecting the public. This gamechanging technology will assist officers to apprehend and prosecute offenders. There is human involvement in each stage of the procedure and no arrest or charge would be taken without trained officers carefully reviewing the output.”