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Law enforcement agencies across the United Kingdom successfully lobbied to use a face scanning system known to be discriminatory against females, youths, and members of minority ethnic backgrounds, following complaints that a less biased version produced fewer potential suspects.

The Technology in Practice

UK forces utilize the police national database (PND) to carry out retrospective facial recognition searches. This process involves matching a reference photograph of a person of interest against a repository of more than 19 million custody photos to identify possible hits.

Acknowledged Discrimination

The UK interior ministry admitted last week that the technology was biased. This acknowledgment came after a review by the government's National Physical Laboratory determined it incorrectly matched people of Black and Asian heritage and women at significantly higher rates than white men. The Home Office said it “had acted on the findings”.

“This raises the issue of whether facial recognition only becomes useful if users tolerate discrimination in ethnicity and sex. Convenience is a poor argument for overriding basic freedoms.”

Long-Standing Problem

Internal documents show that this bias has been known about for more than a year. Furthermore, police forces lobbied to reverse an earlier ruling that was designed to address the problem.

Police bosses were informed of the algorithmic discrimination in late 2024. The government-ordered laboratory study found the system was had a higher probability to produce incorrect matches 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 accuracy setting required for possible hits be increased to a level where the disparity was greatly diminished.

However, this directive was reversed the following month following complaints from police that the adjusted system was generating fewer “useful lines of inquiry”. NPCC documents show the higher threshold cut the number of queries that yielded potential matches from 56% to a mere under 15%.

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 produce false positives for women of Black heritage almost 100 times more often than for white women at specific configurations.

The ministry commented on these results: “Our evaluation found that in a limited set of circumstances the software is more likely to incorrectly include some demographic groups in its search results.”

Operational Effectiveness vs. Bias

Outlining the effect of the brief increase to the system's confidence threshold, the police records state: “The change significantly reduces the impact of bias across protected characteristics of ethnicity, generation and sex but had a significant negative impact on police efficiency”. The papers further note that forces complained that “a once effective tactic returned outcomes of questionable value”.

Broader Rollout Plans

Meanwhile, the UK administration has opened a ten-week public review on its proposals to expand the use of biometric scanning systems. Policing minister Sarah Jones has labeled the tool as the “most significant advance since genetic fingerprinting”.

Expert and Oversight Concerns

Abimbola Johnson, chair of the advisory panel for the national policing equality strategy, said: “There was very little consideration through race action plan meetings of the facial recognition rollout even with obvious cross-over with the strategy's goals.

“This disclosure show yet again that the anti-racism commitments the police has made via the race action plan are failing to be integrated into wider practice. Our reports have warned that innovative tools are being implemented in a context where ethnic inequalities, inadequate oversight and faulty information gathering already persist.

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

Home Office Response

A government representative stated: “We takes the conclusions of the study seriously and we have implemented changes. A updated software has been externally evaluated and procured, which has demonstrated no measurable discrimination. It will be trialled early next year and will be subject to further assessment.

“The foremost aim is ensuring public safety. This gamechanging technology will assist officers to apprehend and prosecute offenders. There is human involvement in every step of the procedure and no further action would be taken without specialist personnel meticulously examining the results.”