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Law enforcement agencies across the United Kingdom effectively campaigned to use a facial recognition system known to be discriminatory against females, young people, and members of minority ethnic backgrounds, after complaining that a more accurate version produced fewer investigative leads.

The Technology in Practice

UK forces utilize the police national database (PND) to carry out searches using historical face recognition. This process involves matching a reference photograph of a suspect against a database of over 19 million mugshots to identify possible hits.

Acknowledged Discrimination

The Home Office conceded last week that the technology was flawed. This admission came after a review by the National Physical Laboratory (NPL) found it misidentified Black and Asian people and females at significantly higher rates than Caucasian males. The Home Office said it “took steps on the findings”.

“It prompts the question of whether this technology only becomes useful if users tolerate discrimination in race and gender. Operational ease is a poor argument for disregarding fundamental rights.”

Long-Standing Problem

Internal documents show 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 notified of the system's bias in September 2024. The government-ordered laboratory study concluded the system was had a higher probability to suggest false positives for images depicting females, individuals of Black ethnicity, and those under 40 years old.

A Reversed Decision

In reaction, the national police leadership body ordered that the confidence threshold required for potential matches be raised to a level where the disparity was significantly reduced.

However, this decision was overturned the following month following complaints from police that the modified technology was generating a lower number of “useful lines of inquiry”. Internal records indicate the stricter setting reduced the proportion of queries resulting in possible identifications from over half to a mere under 15%.

Severe Disparities

Although the authorities refused to say what setting is currently used, the latest independent review found the system could produce incorrect matches for Black women almost 100 times more frequently than for white women at certain settings.

The ministry commented on these results: “The testing identified that in a limited set of circumstances the algorithm is more likely to wrongly flag some population segments in its match reports.”

Operational Effectiveness vs. Bias

Outlining the effect of the temporary raise to the system's accuracy setting, the police records state: “This adjustment greatly lessens the impact of discrimination across legally safeguarded attributes of race, generation and gender but had a substantially detrimental effect on police efficiency”. The papers add that forces complained that “a previously useful tool returned results of questionable value”.

Wider Implementation Proposals

Meanwhile, the government has launched a two-and-a-half-month consultation on its proposals to widen the use of biometric scanning systems. Policing minister the relevant minister has described the tool as the “most significant advance since genetic fingerprinting”.

Expert and Oversight Concerns

Abimbola Johnson, head of the independent scrutiny and oversight board for the national policing equality strategy, said: “There was scant consideration in equality strategy sessions of the facial recognition rollout despite obvious cross-over with the strategy's goals.

“This disclosure show once again that the anti-racism commitments the police has undertaken through the race action plan are not being translated into broader operations. Our reports have warned that innovative tools are being implemented in a context where racial disparities, weak scrutiny and faulty information gathering already persist.

“Any use of this technology must meet rigorous official guidelines, be subject to external review, and demonstrate it reduces rather than compounds ethnic bias.”

Official Statement

A government representative stated: “We treat the findings of the report with utmost gravity and we have implemented changes. A new algorithm has been independently tested and procured, which has demonstrated no measurable discrimination. It will be tested early next year and will be undergo further assessment.

“The foremost aim is ensuring public safety. This gamechanging technology will assist officers to apprehend and prosecute offenders. There is officer review in every step of the process and no arrest or charge would be taken without specialist personnel meticulously examining the output.”