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

How the System Works

British police utilize the national police database to carry out retrospective facial recognition searches. This procedure entails matching a reference photograph of a suspect against a database of over 19 million custody photos to find possible hits.

Admitted Bias

The Home Office admitted last week that the technology was flawed. This admission followed a review by the government's National Physical Laboratory determined it misidentified Black and Asian people and women at significantly higher rates than white men. The ministry stated it “took steps on the findings”.

“It prompts the question of whether facial recognition only becomes effective if users tolerate biases in ethnicity and sex. Operational ease is a weak argument for disregarding fundamental rights.”

Long-Standing Problem

Internal documents show that this discriminatory flaw has been known about for over twelve months. Furthermore, police forces lobbied to reverse an initial decision that was designed to mitigate the problem.

Senior officers were informed of the algorithmic discrimination in late 2024. The Home Office-commissioned laboratory study concluded the system was more likely to produce incorrect matches for photos of females, individuals of Black ethnicity, and those aged 40 and under.

A Policy U-Turn

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

However, this decision was reversed the next month following complaints from police that the adjusted system was producing a lower number of “useful lines of inquiry”. Internal records indicate the stricter setting cut the proportion of searches that yielded possible identifications from 56% to a just 14%.

Profound Inequalities

Although the authorities declined to specify what setting is now in operation, the recent independent review found the system could generate incorrect matches for women of Black heritage nearly a hundred times more frequently than for white women at certain settings.

The Home Office commented on these findings: “Our evaluation identified that in a specific scenarios the software is more likely to wrongly flag some population segments in its match reports.”

Operational Effectiveness vs. Bias

Describing the impact of the temporary raise to the system's confidence threshold, the police records state: “This adjustment greatly lessens the impact of discrimination across legally safeguarded attributes of ethnicity, generation and gender but had a significant negative impact on operational effectiveness”. The papers further note that forces complained that “a once effective tactic returned results of questionable value”.

Broader Rollout Plans

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 Sarah Jones has described the technology as the “most significant advance since genetic fingerprinting”.

Expert and Oversight Concerns

The chair of a police oversight board, head of the advisory panel for the national policing equality strategy, said: “We observed very little consideration through equality strategy sessions of the technology deployment even with obvious cross-over with the plan’s concerns.

“These revelations show yet again that the pledges to combat discrimination the police has undertaken through the equality initiative are not being translated into wider practice. Independent assessments have cautioned that innovative tools are being implemented in a context where racial disparities, inadequate oversight and faulty information gathering already persist.

“All deployment of this technology must adhere to strict national standards, be independently scrutinised, and demonstrate it reduces rather than compounds ethnic bias.”

Official Statement

A government representative said: “We treat the conclusions of the report seriously and we have implemented changes. A updated software has been externally evaluated and acquired, which has demonstrated no measurable discrimination. It will be tested early next year and will be undergo evaluation.

“The foremost aim is ensuring public safety. This gamechanging technology will support officers to apprehend and prosecute offenders. There is officer review in each stage of the process and no further action would be pursued without specialist personnel carefully reviewing the output.”