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Law enforcement agencies across the UK effectively campaigned to deploy a face scanning system acknowledged as biased against women, youths, and individuals from minority ethnic backgrounds, following complaints that a more accurate version generated a reduced number of potential suspects.

The Technology in Practice

British police use the police national database (PND) to conduct retrospective facial recognition searches. This process entails comparing a reference photograph of a suspect against a database of over 19 million mugshots to identify potential matches.

Admitted Bias

The Home Office admitted last week that the system was flawed. This admission followed a study 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 stated it “had acted on the findings”.

“It prompts the issue of whether this technology only becomes effective if users accept discrimination in race and sex. Convenience is a poor argument for overriding fundamental rights.”

Long-Standing Problem

Internal documents reveal that this discriminatory flaw has been recognized for over twelve months. Furthermore, police forces argued to overturn an initial decision that was intended to address the problem.

Police bosses were informed of the system's bias in late 2024. The government-ordered laboratory study concluded the system was more likely to suggest false positives for images depicting females, Black people, and those aged 40 and under.

A Reversed Decision

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

However, this decision was overturned the following month after forces complained that the adjusted system was generating fewer “useful lines of inquiry”. Internal records indicate the higher threshold reduced the number of queries that yielded possible identifications from 56% to a just under 15%.

Profound Inequalities

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

The ministry commented on these findings: “Our evaluation found that in a limited set of circumstances the software is has a greater tendency to wrongly flag some demographic groups in its match reports.”

Balancing Utility and Fairness

Outlining the effect of the temporary raise to the system's accuracy setting, the police records state: “The change greatly lessens the impact of bias across protected characteristics of ethnicity, generation and gender but had a significant negative impact on police efficiency”. The papers add that forces argued that “a previously useful tool returned results of questionable value”.

Wider Implementation Proposals

Meanwhile, the government has launched a two-and-a-half-month public review on its plans to expand the use of facial recognition technology. The minister for police the relevant minister has labeled the technology as the “biggest breakthrough since genetic fingerprinting”.

Expert and Oversight Concerns

The chair of a police oversight board, chair of the advisory panel for the police race action plan, commented: “We observed very little consideration in race action plan meetings of the facial recognition rollout even with clear relevance with the plan’s concerns.

“This disclosure show yet again that the pledges to combat discrimination policing has made through the race action plan are failing to be integrated into broader operations. Our reports have cautioned that new technologies are being implemented in a context where racial disparities, inadequate oversight and faulty information gathering already persist.

“Any use of facial recognition must meet rigorous official guidelines, be independently scrutinised, and demonstrate it diminishes rather than compounds racial disparity.”

Official Statement

A Home Office spokesperson stated: “We treat the conclusions of the report with utmost gravity and we have already taken action. A new algorithm has been independently tested and acquired, which has demonstrated no measurable discrimination. It will be trialled in the coming months and will be undergo further assessment.

“The foremost aim is ensuring public safety. This revolutionary tool will assist police to put criminals and rapists behind bars. There is human involvement in each stage of the process and no arrest or charge would be taken without trained officers meticulously examining the results.”