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Police forces across the UK effectively campaigned to deploy a face scanning system known to be discriminatory against females, youths, and members of ethnic minority groups, after complaining that a less biased version generated fewer potential suspects.

How the System Works

British police utilize the national police database to conduct searches using historical face recognition. This procedure entails matching a reference photograph of a person of interest against a database of more than 19 million custody photos to identify potential matches.

Admitted Bias

The Home Office admitted last week that the system was flawed. This acknowledgment came after a review by the government's National Physical Laboratory determined it misidentified people of Black and Asian heritage and females at significantly higher rates than Caucasian males. The Home Office stated it “had acted on the findings”.

“It prompts the question of whether facial recognition only becomes effective if users accept discrimination in race and gender. Convenience is a poor argument for overriding fundamental rights.”

Known Issue

Official papers reveal that this bias has been known about for over twelve months. Furthermore, police forces lobbied to reverse an initial decision that was intended to address the problem.

Police bosses were notified of the algorithmic discrimination in late 2024. The Home Office-commissioned laboratory study concluded the system was had a higher probability to suggest false positives for photos of females, Black people, and those under 40 years old.

A Policy U-Turn

In reaction, the national police leadership body mandated that the confidence threshold required for potential matches be increased to a point where the bias was significantly reduced.

However, this directive was overturned the next month following complaints from police that the adjusted system was producing a lower number of “useful lines of inquiry”. NPCC documents indicate the stricter setting reduced the proportion of searches that yielded potential matches from 56% to a mere under 15%.

Severe Disparities

Although the authorities declined to specify what threshold is currently used, the recent independent review discovered the system could produce incorrect matches for women of Black heritage nearly a hundred times more often than for white women at certain settings.

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

Operational Effectiveness vs. Bias

Describing the impact of the temporary raise to the system's accuracy setting, the police records note: “This adjustment greatly lessens the impact of discrimination across legally safeguarded attributes of ethnicity, generation and gender but had a substantially detrimental effect on police efficiency”. The papers further note that police units complained that “a once effective tactic returned outcomes of limited benefit”.

Broader Rollout Plans

Meanwhile, the UK administration has launched a ten-week public review on its proposals 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 DNA matching”.

Expert and Oversight Concerns

The chair of a police oversight board, head of the advisory panel for the police race action plan, said: “We observed very little discussion through race action plan meetings of the facial recognition rollout despite obvious cross-over with the plan’s concerns.

“These revelations demonstrate yet again that the anti-racism commitments policing has made via the equality initiative are failing to be integrated into broader operations. Independent assessments have cautioned that innovative tools are being rolled out in a landscape where racial disparities, inadequate oversight and faulty information gathering already persist.

“Any use of this technology must meet rigorous official guidelines, be independently scrutinised, and prove it reduces rather than compounds racial disparity.”

Official Statement

A government representative stated: “We takes the findings of the report with utmost gravity and we have implemented changes. A new algorithm has been independently tested and acquired, which has no statistically significant bias. It will be tested early next year and will be subject to evaluation.

“Our priority is ensuring public safety. This revolutionary tool will support officers to apprehend and prosecute offenders. There is officer review in every step of the process and no arrest or charge would be taken without trained officers carefully reviewing the output.”