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Law enforcement agencies across the UK effectively campaigned to use a facial recognition system known to be discriminatory against women, young people, and members of ethnic minority groups, following complaints that a more accurate version produced fewer investigative leads.

How the System Works

British police utilize the national police database to conduct retrospective facial recognition searches. This process entails comparing a reference photograph of a person of interest against a database of over 19 million custody photos to identify potential matches.

Admitted Bias

The UK interior ministry conceded last week that the system was biased. This admission came after a review by the government's National Physical Laboratory found it incorrectly matched people of Black and Asian heritage and females at significantly higher rates than Caucasian males. The Home Office said it “took steps on the findings”.

“It prompts the issue of whether facial recognition only becomes effective if users accept biases in ethnicity and gender. Operational ease is a weak argument for disregarding fundamental rights.”

Long-Standing Problem

Official papers show that this bias has been known about for more than a year. Furthermore, police forces argued to overturn an initial decision that was intended to mitigate the problem.

Senior officers were notified of the algorithmic discrimination in September 2024. The government-ordered NPL review concluded the system was had a higher probability to suggest incorrect matches for photos of women, Black people, and those aged 40 and under.

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 significantly reduced.

However, this decision was reversed the following month after forces complained that the adjusted system was producing a lower number of “investigative leads”. NPCC documents indicate the stricter setting reduced the number of queries resulting in potential matches from 56% to a just 14%.

Severe Disparities

Although the Home Office and NPCC refused to say what setting is currently used, the recent NPL study found the system could produce false positives for women of Black heritage almost 100 times more frequently than for Caucasian women at certain settings.

The Home Office stated on these findings: “The testing found that in a specific scenarios the algorithm is more likely to incorrectly include some demographic groups in its search results.”

Operational Effectiveness vs. Bias

Outlining the effect of the temporary raise to the system's accuracy setting, the police records state: “The change greatly lessens the impact of discrimination across protected characteristics of race, age and gender but had a significant negative impact on police efficiency”. The documents further note that forces complained that “a previously useful tool returned outcomes of limited benefit”.

Broader Rollout Plans

Meanwhile, the government has launched a ten-week consultation on its proposals to widen the use of facial recognition technology. The minister for police the relevant minister has labeled the technology as the “most significant advance since DNA matching”.

Criticism from Advisors and Monitors

The chair of a police oversight board, chair of the independent scrutiny and oversight board for the police race action plan, said: “There was very little discussion through equality strategy sessions of the facial recognition rollout despite clear relevance with the plan’s concerns.

“These revelations demonstrate once again that the pledges to combat discrimination policing has undertaken through the equality initiative are not being translated into wider practice. Our reports have warned that innovative tools are being implemented in a landscape where racial disparities, inadequate oversight and faulty information gathering already persist.

“Any use of facial recognition must adhere to strict national standards, be subject to external review, and demonstrate it reduces rather than compounds racial disparity.”

Official Statement

A Home Office spokesperson stated: “We treat the conclusions of the report with utmost gravity and we have already taken action. A updated software has been externally evaluated and acquired, which has demonstrated no measurable discrimination. 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 officers 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 meticulously examining the output.”