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Law enforcement agencies across the UK effectively campaigned to use a facial recognition system known to be discriminatory against women, youths, and members of ethnic minority groups, after complaining that a more accurate version generated a reduced number of potential suspects.

How the System Works

UK forces utilize the national police database to conduct searches using historical face recognition. This process involves comparing a reference photograph of a person of interest against a database of over 19 million mugshots to find potential matches.

Acknowledged Discrimination

The Home Office admitted last week that the technology was flawed. This acknowledgment came after a study by the government's National Physical Laboratory determined it misidentified people of Black and Asian heritage and women at much greater frequency than white men. The ministry stated it “took steps on the findings”.

“This raises the question of whether facial recognition only becomes effective if users accept biases in ethnicity and gender. Operational ease is a poor argument for overriding basic freedoms.”

Known Issue

Official papers show that this discriminatory flaw has been known about for over twelve months. Furthermore, law enforcement argued to overturn an initial decision that was intended to address the problem.

Police bosses were informed of the system's bias in September 2024. The Home Office-commissioned NPL review found the system was had a higher probability to produce 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 potential matches be raised to a point where the bias was greatly diminished.

However, this decision was reversed the following month following complaints from police that the modified technology was generating fewer “investigative leads”. NPCC documents show the stricter setting cut the number of queries that yielded possible identifications from 56% to a just under 15%.

Profound Inequalities

Although the authorities refused to say what threshold is currently used, the recent independent review discovered the system could produce false positives for Black women nearly a hundred times more frequently than for white women at certain settings.

The ministry stated on these findings: “Our evaluation found that in a specific scenarios the software is has a greater tendency to incorrectly include some population segments in its match reports.”

Operational Effectiveness vs. Bias

Outlining the impact of the brief increase to the system's confidence threshold, the police records state: “The change greatly lessens the effect of bias across legally safeguarded attributes of race, age and sex but had a substantially detrimental effect on police efficiency”. The papers further note that police units argued that “a once effective tactic now delivered outcomes of limited benefit”.

Broader Rollout Plans

Meanwhile, the government has opened a two-and-a-half-month consultation on its plans to expand the use of facial recognition technology. The minister for police 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 equality strategy sessions of the facial recognition rollout 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 failing to be integrated into wider practice. Independent assessments have warned that new technologies are being rolled out in a context where racial disparities, weak scrutiny and poor data collection continue to exist.

“Any use of facial recognition must adhere to strict national standards, be subject to external review, and prove it reduces rather than compounds ethnic bias.”

Home Office Response

A government representative stated: “We takes the findings of the study with utmost gravity and we have implemented changes. A new algorithm has been independently tested and procured, which has no statistically significant bias. It will be tested early next year and will be undergo further assessment.

“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 procedure and no arrest or charge would be taken without trained officers meticulously examining the output.”