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Police forces across the United Kingdom effectively campaigned to use a facial recognition system acknowledged as biased against females, youths, and members of ethnic minority groups, after complaining that a less biased version produced fewer investigative leads.

How the System Works

UK forces utilize the national police database to conduct searches using historical face recognition. This process entails comparing a “probe image” of a suspect against a repository of more than 19 million custody photos to find potential matches.

Acknowledged Discrimination

The UK interior ministry admitted last week that the system was flawed. This admission came after 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 ministry stated it “took steps on the findings”.

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

Known Issue

Internal documents reveal that this bias has been recognized for over twelve months. Furthermore, police forces lobbied to reverse an initial decision that was designed to address the problem.

Senior officers were notified of the algorithmic discrimination in September 2024. The Home Office-commissioned laboratory study concluded the system was had a higher probability to suggest false positives for photos of women, Black people, and those under 40 years old.

A Reversed Decision

In response, the national police leadership body ordered that the confidence threshold required for possible hits be increased to a point where the bias was greatly diminished.

However, this decision was overturned the following month after forces complained that the adjusted system was generating fewer “useful lines of inquiry”. Internal records indicate the stricter setting cut the number of queries resulting in potential matches from over half to a mere 14%.

Profound Inequalities

Although the authorities refused to say what threshold is now in operation, the recent independent review discovered the system could generate incorrect matches for Black women nearly a hundred times more frequently than for white women at certain settings.

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

Operational Effectiveness vs. Bias

Describing the impact of the brief increase to the system's accuracy setting, the police records note: “This adjustment greatly lessens the effect of discrimination across protected characteristics of ethnicity, age and sex but had a significant negative impact on police efficiency”. The documents add that police units complained that “a previously useful tool returned results of limited benefit”.

Wider Implementation Proposals

Meanwhile, the government has launched a two-and-a-half-month public review on its plans 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”.

Expert and Oversight Concerns

The chair of a police oversight board, chair of the independent scrutiny and oversight board for the police race action plan, commented: “We observed scant consideration through race action plan meetings of the facial recognition rollout even with clear relevance with the strategy's goals.

“These revelations demonstrate once again that the anti-racism commitments the police has made through the equality initiative are not being translated into broader operations. Our reports have warned that new technologies are being implemented in a context where racial disparities, weak scrutiny and faulty information gathering already persist.

“All deployment of this technology must adhere to strict national standards, be subject to external review, and prove it diminishes rather than compounds ethnic bias.”

Official Statement

A Home Office spokesperson said: “The Home Office takes the findings of the study seriously and we have implemented changes. A updated software has been independently tested and acquired, which has demonstrated no measurable discrimination. It will be tested in the coming months and will be subject to evaluation.

“The foremost aim is protecting the public. This gamechanging technology will support officers to apprehend and prosecute offenders. There is human involvement in each stage of the procedure and no arrest or charge would be taken without trained officers carefully reviewing the output.”