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Law enforcement agencies across the United Kingdom successfully lobbied to deploy a facial recognition system known to be biased against women, youths, and members of ethnic minority groups, following complaints that a more accurate version produced a reduced number of potential suspects.

The Technology in Practice

UK forces utilize the national police database to carry out retrospective facial recognition searches. This procedure entails comparing a “probe image” of a suspect against a repository of over 19 million mugshots to identify possible hits.

Acknowledged Discrimination

The UK interior ministry conceded last week that the system was flawed. This admission followed a study by the government's National Physical Laboratory found it misidentified Black and Asian people and females at significantly higher rates than Caucasian males. The ministry stated it “took steps on the findings”.

“It prompts the question of whether this technology only becomes effective if users tolerate discrimination in ethnicity and gender. Convenience is a poor argument for overriding fundamental rights.”

Known Issue

Internal documents reveal that this discriminatory flaw has been known about for over twelve months. Furthermore, law enforcement lobbied to reverse an earlier ruling that was intended to mitigate the problem.

Police bosses were informed of the system's bias in September 2024. The Home Office-commissioned NPL review found the system was more likely to suggest false positives for photos of women, individuals of Black ethnicity, and those under 40 years old.

A Policy U-Turn

In response, the national police leadership body ordered that the confidence threshold required for possible hits be raised to a level where the disparity was significantly reduced.

However, this decision was overturned the following month after forces complained that the modified technology was generating a lower number of “useful lines of inquiry”. NPCC documents indicate the stricter setting reduced the number of queries that yielded possible identifications from over half to a just 14%.

Profound Inequalities

Although the authorities declined to specify what setting is now in operation, the latest NPL study discovered the system could produce incorrect matches for Black women almost 100 times more often than for white women at specific configurations.

The Home Office stated on these results: “The testing identified that in a limited set of circumstances the software is has a greater tendency to incorrectly include some population segments in its match reports.”

Balancing Utility and Fairness

Outlining the impact of the temporary raise to the system's accuracy setting, the NPCC documents state: “The change significantly reduces the effect of discrimination across protected characteristics of ethnicity, age and gender but had a substantially detrimental effect on operational effectiveness”. The documents add that forces complained that “a previously useful tool now delivered outcomes of limited benefit”.

Broader Rollout Plans

Meanwhile, the UK administration has launched a ten-week public review on its proposals to widen the use of biometric scanning systems. The minister for police the relevant minister has described the tool as the “biggest breakthrough since genetic fingerprinting”.

Expert and Oversight Concerns

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

“This disclosure demonstrate yet again that the anti-racism commitments policing has undertaken via the race action plan are not being translated into wider practice. Our reports have cautioned that new technologies are being implemented in a landscape where ethnic inequalities, weak scrutiny and poor data collection already persist.

“All deployment of facial recognition must adhere to strict national standards, be subject to external review, and demonstrate it diminishes rather than exacerbates ethnic bias.”

Home Office Response

A Home Office spokesperson said: “We treat the conclusions of the study with utmost gravity and we have implemented changes. A updated software has been independently tested and procured, which has no statistically significant bias. It will be tested early next year and will be subject to further assessment.

“The foremost aim is protecting the public. This gamechanging technology will assist police to apprehend and prosecute offenders. There is officer review in each stage of the procedure and no further action would be taken without trained officers carefully reviewing the results.”