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Law enforcement agencies across the UK effectively campaigned to use a face scanning system acknowledged as biased against women, youths, and individuals from minority ethnic backgrounds, following complaints that a less biased version generated fewer potential suspects.

The Technology in Practice

UK forces utilize the police national database (PND) to carry out searches using historical face recognition. This procedure entails matching a “probe image” of a person of interest against a database of more than 19 million mugshots to find potential matches.

Admitted Bias

The UK interior ministry conceded last week that the technology was biased. This acknowledgment came after a study by the government's National Physical Laboratory determined it misidentified people of Black and Asian heritage and females at significantly higher rates than white men. The Home Office said it “had acted on the findings”.

“This raises the question of whether this technology only becomes useful if users accept biases in race and gender. Convenience is a poor argument for overriding basic freedoms.”

Known Issue

Official papers reveal that this discriminatory flaw has been recognized for over twelve months. Furthermore, law enforcement lobbied to reverse an earlier ruling that was designed to address the problem.

Senior officers were notified of the algorithmic discrimination in late 2024. The government-ordered laboratory study concluded the system was more likely to suggest incorrect matches for photos of females, Black people, and those aged 40 and under.

A Policy U-Turn

In response, the National Police Chiefs’ Council (NPCC) mandated that the confidence threshold required for possible hits be increased to a point where the bias was significantly reduced.

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

Severe Disparities

Although the authorities declined to specify what setting is currently used, the latest independent review discovered the system could generate incorrect matches for women of Black heritage almost 100 times more often than for white women at specific configurations.

The Home Office commented on these results: “Our evaluation found that in a specific scenarios the algorithm is more likely to wrongly flag some population segments in its match reports.”

Operational Effectiveness vs. Bias

Outlining the impact of the brief increase to the system's accuracy setting, the police records state: “This adjustment greatly lessens the effect of discrimination across legally safeguarded attributes of ethnicity, age and sex but had a significant negative impact on operational effectiveness”. The papers further note that police units complained that “a once effective tactic now delivered results of limited benefit”.

Broader Rollout Plans

Meanwhile, the UK administration has launched a ten-week public review on its proposals to expand the use of facial recognition technology. Policing minister Sarah Jones has labeled the tool as the “biggest breakthrough since genetic fingerprinting”.

Expert and Oversight Concerns

The chair of a police oversight board, chair 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 obvious cross-over with the strategy's goals.

“This disclosure show yet again that the anti-racism commitments policing has undertaken through the race action plan are not being translated into broader operations. Independent assessments have warned that innovative tools are being rolled out in a context where racial disparities, inadequate oversight and poor data collection already persist.

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

Official Statement

A government representative said: “The Home Office treat the findings of the study with utmost gravity and we have already taken action. A new algorithm has been externally evaluated and procured, which has demonstrated no measurable discrimination. It will be tested in the coming months and will be subject to further assessment.

“Our priority is ensuring public safety. This gamechanging technology will support 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 trained officers meticulously examining the results.”