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Police forces across the United Kingdom effectively campaigned to deploy a face scanning system acknowledged as biased against females, young people, and members of minority ethnic backgrounds, after complaining that a more accurate version produced a reduced number of potential suspects.

The Technology in Practice

British police utilize the national police database to conduct retrospective facial recognition searches. This process entails matching a reference photograph of a person of interest against a database of over 19 million mugshots to find potential matches.

Acknowledged Discrimination

The UK interior ministry admitted last week that the system was biased. This acknowledgment followed a study 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 ministry stated it “had acted on the findings”.

“This raises the question of whether this technology only becomes effective if users tolerate discrimination in ethnicity and gender. Convenience is a weak argument for disregarding basic freedoms.”

Long-Standing Problem

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

Senior officers were informed of the system's bias in late 2024. The Home Office-commissioned NPL review found the system was had a higher probability to produce incorrect matches for images depicting females, individuals of Black ethnicity, and those aged 40 and under.

A Policy U-Turn

In reaction, the National Police Chiefs’ Council (NPCC) mandated that the confidence threshold required for possible hits be increased to a point where the bias was greatly diminished.

However, this directive was overturned the next month after forces complained that the modified technology was producing a lower number of “investigative leads”. Internal records show the stricter setting cut the number of searches resulting in possible identifications from 56% to a just 14%.

Profound Inequalities

Although the Home Office and NPCC declined to specify what setting is currently used, the recent independent review discovered the system could produce incorrect matches for Black women nearly a hundred times more often than for white women at specific configurations.

The ministry stated on these findings: “Our evaluation identified that in a specific scenarios the algorithm is has a greater tendency to incorrectly include some population segments in its search results.”

Balancing Utility and Fairness

Outlining the effect of the temporary raise to the system's confidence threshold, the NPCC documents state: “This adjustment greatly lessens the effect of bias across legally safeguarded attributes of ethnicity, age and gender but had a substantially detrimental effect on operational effectiveness”. The documents add that police units complained that “a once effective tactic now delivered outcomes of questionable value”.

Broader Rollout Plans

Meanwhile, the government has launched a two-and-a-half-month consultation on its plans to expand 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 independent scrutiny and oversight board for the police race action plan, said: “There was scant discussion through equality strategy sessions of the technology deployment despite obvious cross-over with the plan’s concerns.

“These revelations show once again that the pledges to combat discrimination policing has undertaken via the equality initiative are not being translated into wider practice. Independent assessments have cautioned that innovative tools are being rolled out in a landscape where racial disparities, inadequate oversight and poor data collection already persist.

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

Official Statement

A government representative stated: “We treat the findings of the report with utmost gravity and we have implemented changes. A updated software has been externally evaluated and acquired, which has demonstrated no measurable discrimination. It will be tested in the coming months and will be undergo further assessment.

“The foremost aim is ensuring public safety. This revolutionary tool will support officers to apprehend and prosecute offenders. There is human involvement in each stage of the procedure and no further action would be taken without trained officers carefully reviewing the results.”