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Law enforcement agencies across the UK effectively campaigned to use a facial recognition system known to be biased against females, young people, and individuals from minority ethnic backgrounds, after complaining that a more accurate version produced a reduced number of potential suspects.

The Technology in Practice

UK forces utilize the national police database to conduct retrospective facial recognition searches. This procedure entails matching a reference photograph of a person of interest against a repository of over 19 million mugshots to identify potential matches.

Acknowledged Discrimination

The UK interior ministry conceded last week that the system was biased. This admission came after a study by the government's National Physical Laboratory determined it misidentified Black and Asian people and females at significantly higher rates than white men. The ministry said it “took steps on the findings”.

“It prompts the issue of whether facial recognition only becomes useful if users tolerate discrimination in ethnicity and gender. Operational ease is a poor argument for overriding fundamental rights.”

Known Issue

Official papers 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 mitigate the problem.

Senior officers were notified of the algorithmic discrimination in late 2024. The government-ordered NPL review concluded the system was had a higher probability to suggest false positives for images depicting women, individuals of Black ethnicity, and those under 40 years old.

A Policy U-Turn

In reaction, the National Police Chiefs’ Council (NPCC) mandated that the accuracy setting required for possible hits be raised to a point where the disparity was greatly diminished.

However, this decision was reversed the next month following complaints from police that the adjusted system was producing fewer “investigative leads”. NPCC documents indicate the higher threshold reduced the number of queries resulting in possible identifications from 56% to a just 14%.

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 women of Black heritage nearly a hundred times more frequently than for Caucasian women at certain settings.

The ministry stated on these results: “Our evaluation identified that in a specific scenarios the algorithm is has a greater tendency to incorrectly include some demographic groups in its search results.”

Balancing Utility and Fairness

Outlining the impact of the brief increase to the system's confidence threshold, the police records state: “The change greatly lessens the impact of bias across legally safeguarded attributes of ethnicity, generation and sex 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”.

Broader Rollout Plans

Meanwhile, the government has launched a ten-week public review on its proposals to widen the use of facial recognition technology. Policing minister Sarah Jones has labeled the tool as the “biggest breakthrough since genetic fingerprinting”.

Criticism from Advisors and Monitors

Abimbola Johnson, head of the independent scrutiny and oversight board for the police race action plan, said: “We observed scant consideration in race action plan meetings of the technology deployment despite obvious cross-over with the plan’s concerns.

“This disclosure show once again that the pledges to combat discrimination the police has undertaken through the equality initiative are failing to be integrated into broader operations. Independent assessments have cautioned that new technologies are being implemented in a context where racial disparities, inadequate oversight and faulty information gathering continue to exist.

“Any use of this technology must meet strict national standards, be subject to external review, and demonstrate it diminishes rather than exacerbates ethnic bias.”

Home Office Response

A government representative stated: “The Home Office takes the findings of the study with utmost gravity and we have implemented changes. A updated software has been independently tested and acquired, which has demonstrated no measurable discrimination. It will be trialled in the coming months and will be subject to evaluation.

“The foremost aim is protecting the public. This revolutionary tool will assist officers to apprehend and prosecute offenders. There is officer review in each stage of the process and no further action would be pursued without trained officers carefully reviewing the output.”