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Law enforcement agencies across the United Kingdom effectively campaigned to use a facial recognition system known to be discriminatory against women, youths, and members of ethnic minority groups, after complaining that a more accurate 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 involves comparing a “probe image” of a person of interest against a repository of more than 19 million custody photos to find possible hits.

Acknowledged Discrimination

The UK interior ministry conceded last week that the technology was flawed. This acknowledgment came after a review by the National Physical Laboratory (NPL) determined it incorrectly matched people of Black and Asian heritage and females at significantly higher rates than white men. The ministry said it “took steps on the findings”.

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

Long-Standing Problem

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

Police bosses were notified of the system's bias in September 2024. The Home Office-commissioned NPL review found the system was had a higher probability to suggest false positives for images depicting women, Black people, and those aged 40 and under.

A Policy U-Turn

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

However, this decision was overturned the following month following complaints from police that the adjusted system was producing fewer “useful lines of inquiry”. Internal records show the stricter setting cut the number of searches resulting in possible identifications from over half to a mere under 15%.

Severe Disparities

Although the Home Office and NPCC declined to specify what setting is currently used, the recent NPL study discovered the system could generate false positives for women of Black heritage almost 100 times more often than for white women at specific configurations.

The ministry stated on these findings: “The testing identified that in a limited set of circumstances the algorithm is more likely to wrongly flag some demographic groups in its match reports.”

Operational Effectiveness vs. Bias

Outlining the effect of the brief increase to the system's confidence threshold, the police records note: “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 papers further note that forces complained that “a previously useful tool returned results of limited benefit”.

Broader Rollout Plans

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

Expert and Oversight Concerns

Abimbola Johnson, chair of the independent scrutiny and oversight board for the national policing equality strategy, commented: “There was scant discussion through equality strategy sessions of the facial recognition rollout even with clear relevance with the strategy's goals.

“These revelations show yet again that the pledges to combat discrimination policing has undertaken through the race action plan are failing to be integrated into wider practice. Independent assessments have warned that innovative tools are being implemented in a landscape where racial disparities, weak scrutiny and faulty information gathering continue to exist.

“All deployment of facial recognition must adhere to strict national standards, be independently scrutinised, and demonstrate it diminishes rather than exacerbates ethnic bias.”

Home Office Response

A Home Office spokesperson said: “The Home Office takes the findings of the report seriously and we have implemented changes. A new algorithm has been externally evaluated and acquired, which has demonstrated no measurable discrimination. It will be tested early next year and will be undergo evaluation.

“Our priority is protecting the public. This revolutionary tool will assist officers to apprehend and prosecute offenders. There is human involvement in each stage of the procedure and no further action would be taken without trained officers meticulously examining the output.”