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Law enforcement agencies across the UK effectively campaigned to use a face scanning system acknowledged as discriminatory against women, young people, and individuals from minority ethnic backgrounds, after complaining that a less biased version generated a reduced number of investigative leads.

How the System Works

UK forces utilize the national police database to carry out searches using historical face recognition. This process entails matching a “probe image” of a person of interest against a database of over 19 million mugshots to find possible hits.

Acknowledged Discrimination

The Home Office admitted last week that the technology was biased. This acknowledgment came after a review by the government's National Physical Laboratory determined it incorrectly matched people of Black and Asian heritage and females at significantly higher rates than Caucasian males. The ministry said it “had acted on the findings”.

“It prompts the question of whether this technology only becomes effective if users accept biases in ethnicity and sex. Convenience is a poor argument for disregarding fundamental rights.”

Long-Standing Problem

Official papers show that this discriminatory flaw has been recognized for over twelve months. Furthermore, police forces argued to overturn an earlier ruling that was designed to address the problem.

Police bosses were notified of the algorithmic discrimination in late 2024. The Home Office-commissioned laboratory study concluded the system was more likely to suggest false positives for images depicting women, Black people, and those under 40 years old.

A Reversed Decision

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

However, this directive was overturned the next month after forces complained that the adjusted system was producing fewer “useful lines of inquiry”. Internal records indicate the stricter setting cut the proportion of searches resulting in potential matches from over half to a mere 14%.

Severe Disparities

Although the Home Office and NPCC refused to say what setting is now in operation, the latest independent review found the system could generate false positives for women of Black heritage nearly a hundred times more often than for Caucasian women at specific configurations.

The ministry stated on these findings: “Our evaluation identified that in a specific scenarios the software is more likely to incorrectly include some population segments in its match reports.”

Balancing Utility and Fairness

Describing the impact of the brief increase to the system's confidence threshold, the police records state: “This adjustment significantly reduces the effect of discrimination across legally safeguarded attributes of race, generation and gender but had a significant negative impact on operational effectiveness”. The papers add that forces complained that “a previously useful tool returned results of questionable value”.

Broader Rollout Plans

Meanwhile, the government has launched a ten-week consultation on its proposals to expand the use of facial recognition technology. Policing minister the relevant minister has labeled the tool as the “most significant advance since DNA matching”.

Expert and Oversight Concerns

Abimbola Johnson, chair of the independent scrutiny and oversight board for the national policing equality strategy, commented: “We observed scant discussion through equality strategy sessions of the facial recognition rollout even with clear relevance with the plan’s concerns.

“This disclosure demonstrate yet again that the pledges to combat discrimination the police has undertaken via the equality initiative are failing to be integrated into broader operations. Our reports have cautioned that new technologies are being rolled out in a context where ethnic inequalities, weak scrutiny and faulty information gathering already persist.

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

Home Office Response

A Home Office spokesperson said: “We takes the conclusions of the study seriously and we have already taken action. A new algorithm has been externally evaluated and acquired, which has demonstrated no measurable discrimination. It will be trialled in the coming months and will be undergo evaluation.

“Our priority is ensuring public safety. This gamechanging technology will assist police to put criminals and rapists behind bars. There is officer review in every step of the process and no further action would be pursued without specialist personnel carefully reviewing the results.”