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Police forces across the UK effectively campaigned to use a facial recognition system acknowledged as discriminatory against women, youths, and individuals from minority ethnic backgrounds, following complaints that a less biased version generated fewer potential suspects.

The Technology in Practice

UK forces utilize the national police database to conduct retrospective facial recognition searches. This process involves comparing a “probe image” of a person of interest against a repository of over 19 million custody photos to find possible hits.

Admitted Bias

The UK interior ministry conceded last week that the technology was biased. This admission followed a review by the government's National Physical Laboratory determined it incorrectly matched people of Black and Asian heritage and women at much greater frequency than Caucasian males. The ministry said it “had acted on the findings”.

“This raises the issue of whether this technology only becomes effective if users tolerate discrimination in ethnicity and sex. Operational ease is a weak argument for overriding fundamental rights.”

Known Issue

Official papers reveal that this bias has been recognized for over twelve months. Furthermore, law enforcement argued to overturn an earlier ruling that was designed to mitigate the problem.

Senior officers were informed of the system's bias in late 2024. The government-ordered laboratory study found the system was more likely to produce incorrect matches for photos of women, Black people, 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 increased to a point where the bias was greatly diminished.

However, this directive was overturned the following month following complaints from police that the modified technology was producing fewer “investigative leads”. Internal records show the higher threshold cut the number of searches resulting in possible identifications from over half to a mere under 15%.

Profound Inequalities

Although the authorities declined to specify what threshold is now in operation, the latest independent review discovered the system could generate incorrect matches for women of Black heritage nearly a hundred times more often than for white women at specific configurations.

The ministry stated on these results: “The testing found that in a limited set of circumstances the software is more likely to incorrectly include 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 NPCC documents state: “This adjustment greatly lessens the effect of discrimination across legally safeguarded attributes of race, age and gender but had a substantially detrimental effect on operational effectiveness”. The papers add that police units complained that “a previously useful tool now delivered results of limited benefit”.

Wider Implementation Proposals

Meanwhile, the government has launched a two-and-a-half-month consultation on its plans to widen the use of facial recognition technology. Policing minister the relevant minister has labeled the tool as the “biggest breakthrough since DNA matching”.

Expert and Oversight Concerns

The chair of a police oversight board, chair of the advisory panel for the police race action plan, commented: “There was very little discussion through equality strategy sessions of the technology deployment even with obvious cross-over with the strategy's goals.

“These revelations demonstrate yet again that the pledges to combat discrimination the police has made through the equality initiative are failing to be integrated into wider practice. Independent assessments have cautioned that new technologies are being implemented in a landscape where racial disparities, weak scrutiny and poor data collection already persist.

“All deployment of facial recognition must adhere to rigorous official guidelines, be independently scrutinised, and demonstrate it reduces rather than compounds racial disparity.”

Official Statement

A government representative stated: “We treat the conclusions of the report seriously and we have already taken action. A new algorithm has been externally evaluated and acquired, which has no statistically significant bias. It will be trialled early next year and will be subject to further assessment.

“Our priority is ensuring public safety. This gamechanging technology will assist police to apprehend and prosecute offenders. There is officer review in each stage of the procedure and no arrest or charge would be pursued without trained officers carefully reviewing the output.”