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

How the System Works

UK forces utilize the police national database (PND) to carry out retrospective facial recognition searches. This procedure entails matching a “probe image” of a suspect against a database of over 19 million mugshots to identify potential matches.

Admitted Bias

The Home Office 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 women at much greater frequency than white men. The ministry said it “took steps on the findings”.

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

Long-Standing Problem

Internal documents show that this bias has been recognized for more than a year. Furthermore, police forces lobbied to reverse an earlier ruling that was intended to mitigate the problem.

Police bosses were informed of the algorithmic discrimination in September 2024. The Home Office-commissioned laboratory study found the system was had a higher probability to suggest incorrect matches for photos of females, individuals of Black ethnicity, and those aged 40 and under.

A Policy U-Turn

In response, the national police leadership body ordered that the accuracy setting required for possible hits be increased to a point where the disparity was significantly reduced.

However, this decision was overturned the next month following complaints from police that the modified technology was producing a lower number of “useful lines of inquiry”. NPCC documents indicate the stricter setting reduced the number of queries that yielded possible identifications from over half to a just under 15%.

Profound Inequalities

Although the Home Office and NPCC refused to say what setting is now in operation, the latest independent review found the system could generate incorrect matches for women of Black heritage almost 100 times more frequently than for Caucasian women at certain settings.

The Home Office commented on these findings: “The testing identified that in a limited set of circumstances the software is more likely to incorrectly include some demographic groups in its match reports.”

Balancing Utility and Fairness

Outlining the impact of the brief increase to the system's accuracy setting, the NPCC documents state: “The change significantly reduces the impact of discrimination across protected characteristics of race, generation and sex but had a significant negative impact on operational effectiveness”. The papers further note that police units complained that “a previously useful tool now delivered outcomes of limited benefit”.

Broader Rollout Plans

Meanwhile, the government has launched a ten-week public review on its plans to widen the use of facial recognition technology. Policing minister Sarah Jones has labeled the technology as the “most significant advance since DNA matching”.

Criticism from Advisors and Monitors

Abimbola Johnson, head of the independent scrutiny and oversight board for the police race action plan, commented: “There was scant consideration through equality strategy sessions of the facial recognition rollout despite clear relevance with the strategy's goals.

“This disclosure show once again that the anti-racism commitments policing has undertaken through the equality initiative are failing to be integrated into wider practice. Our reports have warned that new technologies are being implemented in a landscape where ethnic inequalities, inadequate oversight and faulty information gathering continue to exist.

“Any use of this technology must meet rigorous official guidelines, be independently scrutinised, and demonstrate it diminishes rather than exacerbates racial disparity.”

Official Statement

A government representative said: “The Home Office treat the findings of the report with utmost gravity and we have implemented changes. A new algorithm has been externally evaluated and procured, which has demonstrated no measurable discrimination. It will be trialled early next year and will be subject to further assessment.

“The foremost aim is protecting the public. This revolutionary tool will assist officers to put criminals and rapists behind bars. There is human involvement in each stage of the procedure and no arrest or charge would be pursued without specialist personnel carefully reviewing the output.”