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Law enforcement agencies across the UK 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 less biased version produced fewer potential suspects.

The Technology in Practice

UK forces utilize the national police database to conduct retrospective facial recognition searches. This procedure entails comparing a “probe image” of a suspect against a database of more than 19 million custody photos to find potential matches.

Admitted Bias

The Home Office admitted last week that the technology was flawed. This acknowledgment followed a review by the government's National Physical Laboratory found it incorrectly matched people of Black and Asian heritage and women at much greater frequency than white men. The Home Office said it “took steps on the findings”.

“It prompts the issue of whether facial recognition only becomes useful if users accept discrimination in ethnicity and sex. Convenience is a weak argument for disregarding fundamental rights.”

Long-Standing Problem

Internal documents show that this discriminatory flaw has been recognized for more than a year. Furthermore, police forces argued to overturn an earlier ruling that was designed 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 had a higher probability to produce false positives for photos of females, individuals of Black ethnicity, and those under 40 years old.

A Reversed Decision

In reaction, the National Police Chiefs’ Council (NPCC) ordered that the confidence threshold required for possible hits be increased to a level where the disparity was greatly diminished.

However, this directive was reversed the following month after forces complained that the adjusted system was generating fewer “useful lines of inquiry”. Internal records indicate the stricter setting cut the number of queries that yielded potential matches from over half to a just 14%.

Severe Disparities

Although the authorities declined to specify what setting is now in operation, the latest NPL study discovered the system could generate false positives for women of Black heritage almost 100 times more frequently than for Caucasian women at specific configurations.

The ministry stated on these results: “Our evaluation identified that in a limited set of circumstances the software is has a greater tendency to wrongly flag some population segments in its search results.”

Operational Effectiveness vs. Bias

Describing the effect of the temporary raise to the system's accuracy setting, the police records state: “This adjustment greatly lessens the effect of bias across protected characteristics of ethnicity, generation and sex but had a significant negative impact on police efficiency”. The documents add that police units argued that “a once effective tactic returned results of limited benefit”.

Wider Implementation Proposals

Meanwhile, the government has opened a two-and-a-half-month public review on its plans to expand the use of biometric scanning systems. Policing minister the relevant minister has labeled the technology as the “most significant advance since genetic fingerprinting”.

Expert and Oversight Concerns

Abimbola Johnson, head of the advisory panel for the national policing equality strategy, said: “There was scant discussion in race action plan meetings of the technology deployment even with obvious cross-over with the plan’s concerns.

“This disclosure demonstrate once again that the pledges to combat discrimination policing has made via the equality initiative are not being translated into wider practice. Our reports have warned that new technologies are being rolled out in a landscape where racial disparities, weak scrutiny and faulty information gathering already persist.

“All deployment of facial recognition must adhere to strict national standards, be subject to external review, and demonstrate it reduces rather than exacerbates ethnic bias.”

Official Statement

A Home Office spokesperson said: “The Home Office takes the conclusions of the report with utmost gravity and we have implemented changes. A updated software has been independently tested and acquired, which has no statistically significant bias. It will be trialled early next year and will be undergo evaluation.

“The foremost aim is ensuring public safety. This gamechanging technology will support officers to put criminals and rapists behind bars. There is officer review in every step of the process and no arrest or charge would be taken without trained officers carefully reviewing the results.”