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Law enforcement agencies across the UK effectively campaigned to deploy a face scanning system acknowledged as discriminatory against women, youths, and individuals from minority ethnic backgrounds, following complaints that a less biased version generated fewer potential suspects.

The Technology in Practice

British police utilize the national police database to carry out searches using historical face recognition. This procedure involves comparing a “probe image” of a person of interest against a database of more than 19 million custody photos to identify potential matches.

Admitted Bias

The Home Office conceded last week that the technology was flawed. This acknowledgment followed a study by the government's National Physical Laboratory found it incorrectly matched people of Black and Asian heritage and females at much greater frequency than white men. The ministry said it “took steps on the findings”.

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

Long-Standing Problem

Official papers reveal that this discriminatory flaw has been recognized for over twelve months. Furthermore, police forces lobbied to reverse an initial decision that was designed to address the problem.

Police bosses were informed of the system's bias in late 2024. The Home Office-commissioned NPL review concluded the system was had a higher probability to produce false positives 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 accuracy setting required for potential matches be raised to a level where the disparity was significantly reduced.

However, this decision was reversed the next month following complaints from police that the modified technology was generating fewer “investigative leads”. NPCC documents show the higher threshold cut the number of searches resulting in potential matches from over half to a just 14%.

Severe Disparities

Although the authorities declined to specify what setting is now in operation, the latest independent review discovered the system could generate false positives for women of Black heritage almost 100 times more frequently than for Caucasian women at certain settings.

The ministry commented on these findings: “Our evaluation found that in a limited set of circumstances the software is more likely to wrongly flag some demographic groups in its match reports.”

Balancing Utility and Fairness

Describing the effect of the brief increase to the system's confidence threshold, the NPCC documents note: “The change significantly reduces the effect of discrimination across protected characteristics of ethnicity, age and gender but had a significant negative impact on operational effectiveness”. The documents add that police units complained that “a previously useful tool returned results of limited benefit”.

Wider Implementation Proposals

Meanwhile, the UK administration has opened a ten-week consultation on its proposals to widen the use of facial recognition technology. The minister for police Sarah Jones has described the technology as the “most significant advance since genetic fingerprinting”.

Expert and Oversight Concerns

Abimbola Johnson, chair of the independent scrutiny and oversight board for the national policing equality strategy, commented: “There was very little consideration through equality strategy sessions of the technology deployment despite obvious cross-over with the strategy's goals.

“These revelations demonstrate yet again that the pledges to combat discrimination the police has made via the race action plan are not being translated into wider practice. Our reports have cautioned that new technologies are being rolled out in a context where ethnic inequalities, inadequate oversight and faulty information gathering continue to exist.

“All deployment of this technology must meet rigorous official guidelines, be independently scrutinised, and demonstrate it reduces rather than exacerbates racial disparity.”

Official Statement

A government representative said: “The Home Office treat the conclusions of the report seriously and we have implemented changes. A updated software has been independently tested and procured, which has no statistically significant bias. It will be trialled in the coming months and will be subject to further assessment.

“Our priority is ensuring public safety. This revolutionary tool will support police to put criminals and rapists behind bars. There is human involvement in every step of the process and no further action would be pursued without specialist personnel meticulously examining the results.”