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Police forces across the United Kingdom effectively campaigned to use a face scanning system known to be discriminatory against females, young people, and individuals from minority ethnic backgrounds, following complaints that a more accurate version generated a reduced number of investigative leads.

How the System Works

British police use the national police database to carry out searches using historical face recognition. This procedure entails comparing a reference photograph of a person of interest against a repository of over 19 million custody photos to find possible hits.

Acknowledged Discrimination

The UK interior ministry admitted last week that the system was flawed. This acknowledgment followed a study by the government's National Physical Laboratory determined it misidentified Black and Asian people and women at significantly higher rates than white men. The Home Office stated it “had acted on the findings”.

“This raises the issue of whether this technology only becomes effective if users tolerate biases in ethnicity and gender. Operational ease is a poor argument for disregarding basic freedoms.”

Known Issue

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

Senior officers were informed of the algorithmic discrimination in September 2024. The government-ordered NPL review concluded the system was more likely to produce incorrect matches for photos of females, individuals of Black ethnicity, and those under 40 years old.

A Reversed Decision

In reaction, the national police leadership body mandated that the accuracy setting required for possible hits be increased to a level where the disparity was significantly reduced.

However, this decision was overturned the following month after forces complained that the adjusted system was producing a lower number of “useful lines of inquiry”. NPCC documents indicate the stricter setting cut the number of searches resulting in possible identifications from over half to a mere 14%.

Profound Inequalities

Although the Home Office and NPCC declined to specify what setting is now in operation, the recent independent review discovered the system could generate false positives for Black women almost 100 times more frequently than for Caucasian women at certain settings.

The ministry commented on these results: “Our evaluation identified that in a limited set of circumstances the software is has a greater tendency to wrongly flag some demographic groups in its search results.”

Balancing Utility and Fairness

Outlining the impact of the temporary raise to the system's confidence threshold, the NPCC documents note: “This adjustment significantly reduces the impact of bias across legally safeguarded attributes of race, age and gender but had a significant negative impact on police efficiency”. The papers further note that police units argued that “a previously useful tool now delivered outcomes of questionable value”.

Wider Implementation Proposals

Meanwhile, the UK administration has opened a two-and-a-half-month public review on its proposals to expand the use of facial recognition technology. Policing minister Sarah Jones has labeled the technology as the “most significant advance since genetic fingerprinting”.

Criticism from Advisors and Monitors

Abimbola Johnson, head of the independent scrutiny and oversight board for the police race action plan, said: “There was scant consideration in equality strategy sessions of the technology deployment despite obvious cross-over with the strategy's goals.

“This disclosure demonstrate once again that the pledges to combat discrimination policing has made via the equality initiative are failing to be integrated into wider practice. Our reports have cautioned that innovative tools are being implemented in a landscape where racial disparities, weak scrutiny and faulty information gathering already persist.

“Any use of facial recognition must adhere to rigorous official guidelines, be subject to external review, and demonstrate it reduces rather than exacerbates racial disparity.”

Official Statement

A government representative stated: “We treat the conclusions of the report with utmost gravity and we have implemented changes. A updated software has been independently tested and acquired, which has no statistically significant bias. It will be trialled in the coming months and will be subject to further assessment.

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