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Law enforcement agencies across the United Kingdom successfully lobbied to use a facial recognition system acknowledged as discriminatory against women, youths, and individuals from ethnic minority groups, after complaining that a less biased version produced fewer potential suspects.

How the System Works

British police utilize the national police database 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 mugshots to identify possible hits.

Acknowledged Discrimination

The Home Office admitted last week that the technology was flawed. This acknowledgment came after a review by the government's National Physical Laboratory determined it incorrectly matched Black and Asian people and women at significantly higher rates than Caucasian males. The ministry stated it “took steps on the findings”.

“It prompts the issue of whether this technology only becomes effective if users tolerate biases in race and sex. Operational ease is a poor argument for disregarding fundamental rights.”

Known Issue

Official papers show that this discriminatory flaw has been known about for over twelve months. Furthermore, law enforcement argued to overturn an initial decision that was intended to address the problem.

Senior officers were informed of the algorithmic discrimination in late 2024. The government-ordered laboratory study found the system was more likely to produce incorrect matches for images depicting women, individuals of Black ethnicity, and those under 40 years old.

A Policy U-Turn

In reaction, the national police leadership body mandated that the confidence threshold required for potential matches be raised to a level where the bias was significantly reduced.

However, this directive was overturned the next month following complaints from police that the modified technology was generating a lower number of “useful lines of inquiry”. Internal records show the stricter setting cut the number of searches that yielded possible identifications from over half to a just 14%.

Profound Inequalities

Although the authorities declined to specify what setting is now in operation, the latest independent review discovered the system could generate incorrect matches for women of Black heritage nearly a hundred times more often than for Caucasian women at specific configurations.

The ministry stated on these findings: “Our evaluation found that in a specific scenarios the algorithm is has a greater tendency to wrongly flag some demographic groups in its match reports.”

Operational Effectiveness vs. Bias

Outlining the effect of the brief increase to the system's confidence threshold, the NPCC documents note: “The change significantly reduces the effect of bias across legally safeguarded attributes of ethnicity, age and gender but had a substantially detrimental effect on operational effectiveness”. The papers add that police units argued that “a once effective tactic now delivered results of questionable value”.

Broader Rollout Plans

Meanwhile, the government has opened a ten-week consultation on its proposals to expand the use of facial recognition technology. The minister for police Sarah Jones has described the technology as the “most significant advance since DNA matching”.

Criticism from Advisors and Monitors

Abimbola Johnson, head of the independent scrutiny and oversight board for the national policing equality strategy, commented: “We observed scant consideration through race action plan meetings of the technology deployment even with clear relevance with the strategy's goals.

“These revelations show once again that the pledges to combat discrimination the police has made via the equality initiative are not being translated into broader operations. Our reports have cautioned that new technologies are being rolled out in a landscape where ethnic inequalities, weak scrutiny and poor data collection already persist.

“All deployment of this technology must adhere to strict national standards, be independently scrutinised, and demonstrate it reduces rather than compounds racial disparity.”

Official Statement

A Home Office spokesperson said: “The Home Office takes the conclusions of the report seriously and we have already taken action. A new algorithm has been externally evaluated and acquired, which has demonstrated no measurable discrimination. It will be trialled in the coming months and will be undergo further assessment.

“The foremost aim is ensuring public safety. This revolutionary tool will assist police to put criminals and rapists behind bars. There is officer review in every step of the process and no further action would be pursued without specialist personnel carefully reviewing the output.”