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Law enforcement agencies across the UK effectively campaigned to deploy a facial recognition system acknowledged as discriminatory against women, youths, and individuals from ethnic minority groups, after complaining that a more accurate version produced fewer investigative leads.

The Technology in Practice

UK forces use the police national database (PND) to conduct retrospective facial recognition searches. This procedure entails matching a reference photograph of a suspect against a repository of over 19 million custody photos to identify potential matches.

Acknowledged Discrimination

The Home Office admitted last week that the system was flawed. This acknowledgment followed a study by the government's National Physical Laboratory determined it incorrectly matched Black and Asian people and women at much greater frequency than white men. The ministry stated it “had acted on the findings”.

“This raises the issue of whether this technology only becomes useful if users accept discrimination in race and gender. Convenience is a weak argument for disregarding basic freedoms.”

Long-Standing Problem

Official papers show that this bias has been recognized for more than a year. Furthermore, police forces argued to overturn an earlier ruling that was designed to address the problem.

Police bosses were informed of the algorithmic discrimination in late 2024. The Home Office-commissioned NPL review concluded the system was had a higher probability to produce incorrect matches for photos of women, individuals of Black ethnicity, and those under 40 years old.

A Policy U-Turn

In reaction, the National Police Chiefs’ Council (NPCC) ordered that the accuracy setting required for possible hits be increased to a point where the disparity was significantly reduced.

However, this directive was overturned the next month after forces complained that the modified technology was generating a lower number of “useful lines of inquiry”. NPCC documents indicate the higher threshold reduced the proportion of searches resulting in possible identifications from over half to a just 14%.

Severe Disparities

Although the Home Office and NPCC refused to say what threshold is currently used, 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 Home Office stated on these results: “Our evaluation identified that in a limited set of circumstances the algorithm is more likely to incorrectly include some population segments in its match reports.”

Balancing Utility and Fairness

Describing the effect of the temporary raise to the system's confidence threshold, the police records state: “The change significantly reduces the effect of bias across legally safeguarded attributes of race, age and gender but had a significant negative impact on operational effectiveness”. The papers further note that police units argued that “a previously useful tool now delivered results of questionable value”.

Wider Implementation Proposals

Meanwhile, the UK administration has opened a ten-week public review on its plans to widen the use of biometric scanning systems. The minister for police Sarah Jones has described the tool as the “biggest breakthrough since DNA matching”.

Expert and Oversight Concerns

Abimbola Johnson, head of the independent scrutiny and oversight board for the police race action plan, said: “There was scant consideration through race action plan meetings of the facial recognition rollout even with obvious cross-over with the strategy's goals.

“These revelations demonstrate once again that the pledges to combat discrimination the police has made through the race action plan are failing to be integrated into broader operations. Independent assessments have warned that new technologies are being implemented in a context where ethnic inequalities, inadequate oversight and faulty information gathering continue to exist.

“Any use of facial recognition must adhere to strict national standards, be independently scrutinised, and prove it diminishes rather than exacerbates ethnic bias.”

Official Statement

A Home Office spokesperson stated: “The Home Office takes the findings of the study seriously and we have implemented changes. A updated software has been externally evaluated and acquired, which has demonstrated no measurable discrimination. It will be tested early next year and will be undergo evaluation.

“The foremost aim is protecting the public. This gamechanging technology will assist police to apprehend and prosecute offenders. There is human involvement in each stage of the process and no further action would be pursued without trained officers meticulously examining the output.”