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Police forces across the United Kingdom successfully lobbied to deploy a facial recognition system acknowledged as discriminatory against females, young people, and members of ethnic minority groups, after complaining that a more accurate version generated a reduced number of investigative leads.

The Technology in Practice

UK forces utilize the national police database to conduct searches using historical face recognition. This process entails comparing a reference photograph of a suspect against a repository of more than 19 million mugshots to identify potential matches.

Admitted Bias

The UK interior ministry admitted last week that the system was flawed. This acknowledgment came after a review by the National Physical Laboratory (NPL) determined it misidentified Black and Asian people and females at much greater frequency than white men. The ministry stated it “had acted on the findings”.

“This raises the issue of whether facial recognition only becomes effective if users accept discrimination in ethnicity and gender. Convenience is a poor argument for overriding fundamental rights.”

Long-Standing Problem

Internal documents show that this discriminatory flaw has been known about for more than a year. Furthermore, police forces lobbied to reverse an initial decision that was intended to mitigate the problem.

Police bosses were informed of the algorithmic discrimination in September 2024. The Home Office-commissioned NPL review found the system was had a higher probability to suggest false positives for photos of females, individuals of Black ethnicity, and those under 40 years old.

A Reversed Decision

In response, the National Police Chiefs’ Council (NPCC) ordered that the accuracy setting required for potential matches be increased to a level where the disparity was significantly reduced.

However, this directive was reversed the next month after forces complained that the modified technology was generating fewer “investigative leads”. NPCC documents indicate the higher threshold cut the proportion of searches resulting in potential matches from 56% to a just 14%.

Severe Disparities

Although the authorities declined to specify what setting is now in operation, the latest independent review found the system could generate false positives for Black women nearly a hundred times more often than for white women at certain settings.

The ministry stated on these results: “Our evaluation found that in a limited set of circumstances the algorithm is more likely to wrongly flag some demographic groups in its search results.”

Operational Effectiveness vs. Bias

Outlining the effect of the temporary raise to the system's accuracy setting, the NPCC documents state: “This adjustment greatly lessens the impact of discrimination across protected characteristics of ethnicity, generation and sex but had a substantially detrimental effect on police efficiency”. The papers add that police units argued that “a previously useful tool now delivered outcomes 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. The minister for police Sarah Jones has labeled the technology as the “most significant advance since DNA matching”.

Expert and Oversight Concerns

Abimbola Johnson, head of the independent scrutiny and oversight board for the police race action plan, commented: “There was very little discussion in equality strategy sessions of the facial recognition rollout even with obvious cross-over with the strategy's goals.

“This disclosure show yet again that the anti-racism commitments the police has undertaken through the race action plan are failing to be integrated into wider practice. Our reports have cautioned that innovative tools are being implemented in a context where ethnic inequalities, inadequate oversight and faulty information gathering continue to exist.

“Any use 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 said: “The Home Office takes the findings of the report with utmost gravity and we have implemented changes. A new algorithm has been externally evaluated and procured, which has no statistically significant bias. It will be trialled early next year and will be undergo evaluation.

“Our priority is ensuring public safety. This revolutionary tool will assist police to apprehend and prosecute offenders. There is human involvement in every step of the procedure and no further action would be taken without trained officers meticulously examining the output.”