🔗 Share this article

Law enforcement agencies across the United Kingdom effectively campaigned to use a facial recognition system known to be discriminatory against females, young people, and individuals from ethnic minority groups, after complaining that a more accurate version generated a reduced number of potential suspects.

How the System Works

UK forces utilize the national police database to carry out retrospective facial recognition searches. This procedure involves matching a “probe image” of a suspect 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 biased. This acknowledgment followed a study by the National Physical Laboratory (NPL) found it misidentified people of Black and Asian heritage and females at much greater frequency than white men. The Home Office said it “took steps on the findings”.

“This raises the question of whether this technology only becomes useful if users tolerate biases in race and sex. Convenience is a poor argument for overriding basic freedoms.”

Long-Standing Problem

Official papers show that this discriminatory flaw has been recognized for more than a year. Furthermore, police forces argued to overturn an initial decision that was designed to address the problem.

Police bosses were notified of the algorithmic discrimination in late 2024. The Home Office-commissioned laboratory study found the system was more likely to produce incorrect matches for images depicting women, Black people, and those under 40 years old.

A Policy U-Turn

In response, the national police leadership body ordered that the accuracy setting required for possible hits be increased to a point where the bias was significantly reduced.

However, this decision was overturned the next month following complaints from police that the modified technology was producing a lower number of “investigative leads”. Internal records indicate the higher threshold cut the proportion of queries that yielded potential matches from 56% to a mere 14%.

Severe Disparities

Although the authorities refused to say what threshold is now in operation, the latest independent review discovered the system could generate false positives for Black women nearly a hundred times more often than for Caucasian women at specific configurations.

The ministry stated on these results: “Our evaluation identified that in a limited set of circumstances the algorithm is more likely to wrongly flag some demographic groups in its match reports.”

Operational Effectiveness vs. Bias

Outlining the effect of the temporary raise to the system's confidence threshold, the police records note: “The change greatly lessens the effect of bias across protected characteristics of race, generation and gender but had a substantially detrimental effect on police efficiency”. The papers further note that forces argued that “a previously useful tool now delivered outcomes of limited benefit”.

Broader Rollout Plans

Meanwhile, the UK administration has launched a ten-week public review on its plans to expand the use of biometric scanning systems. The minister for police the relevant minister has labeled the tool as the “biggest breakthrough since genetic fingerprinting”.

Expert and Oversight Concerns

The chair of a police oversight board, chair of the advisory panel for the national policing equality strategy, said: “We observed scant discussion in equality strategy sessions of the facial recognition rollout despite clear relevance with the plan’s concerns.

“This disclosure show once again that the anti-racism commitments the police has undertaken via the equality initiative are failing to be integrated into wider practice. Independent assessments have warned that innovative tools are being rolled out in a landscape where racial disparities, weak scrutiny and faulty information gathering continue to exist.

“Any use of facial recognition must meet rigorous official guidelines, be subject to external review, and prove it reduces rather than compounds ethnic bias.”

Official Statement

A government representative said: “The Home Office takes the findings of the report with utmost gravity and we have already taken action. A updated software has been externally evaluated and procured, which has demonstrated no measurable discrimination. It will be trialled in the coming months and will be undergo evaluation.

“The foremost aim is ensuring public safety. This revolutionary tool will assist officers to put criminals and rapists behind bars. There is officer review in each stage of the procedure and no further action would be taken without specialist personnel meticulously examining the output.”