🔗 Share this article

Law enforcement agencies across the UK successfully lobbied to use a facial recognition system acknowledged as discriminatory against females, youths, and individuals from ethnic minority groups, following complaints that a less biased version generated fewer potential suspects.

How the System Works

British police utilize the national police database to carry out retrospective facial recognition searches. This process entails comparing a reference photograph 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 acknowledgment came after a study by the government's National Physical Laboratory found it incorrectly matched people of Black and Asian heritage and women at significantly higher rates than white men. The ministry said it “had acted on the findings”.

“This raises the issue of whether facial recognition only becomes effective if users tolerate biases in ethnicity and sex. Convenience is a weak argument for disregarding basic freedoms.”

Long-Standing Problem

Internal documents show that this bias has been recognized for more than a year. Furthermore, law enforcement argued to overturn an earlier ruling that was intended to mitigate the problem.

Senior officers were informed of the system's bias in late 2024. The government-ordered NPL review found the system was had a higher probability to suggest incorrect matches for photos of females, Black people, and those under 40 years old.

A Reversed Decision

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

However, this decision was overturned the following month following complaints from police that the adjusted system was producing fewer “investigative leads”. NPCC documents show the higher threshold reduced the proportion of searches that yielded potential matches from 56% to a mere 14%.

Profound Inequalities

Although the Home Office and NPCC declined to specify what setting is currently used, the latest NPL study discovered the system could generate false positives for women of Black heritage almost 100 times more frequently than for white women at specific configurations.

The ministry stated on these findings: “The testing found that in a specific scenarios the software is has a greater tendency to incorrectly include some population segments in its match reports.”

Balancing Utility and Fairness

Describing the impact of the temporary raise to the system's confidence threshold, the police records note: “The change greatly lessens the effect of discrimination across protected characteristics of race, age and sex but had a substantially detrimental effect on police efficiency”. The papers further note that police units argued that “a once effective tactic now delivered outcomes of questionable value”.

Broader Rollout Plans

Meanwhile, the government has launched a two-and-a-half-month consultation on its plans to widen the use of biometric scanning systems. The minister for police the relevant minister has labeled the technology as the “most significant advance since genetic fingerprinting”.

Criticism from Advisors and Monitors

Abimbola Johnson, head of the advisory panel for the police race action plan, commented: “We observed very little consideration through race action plan meetings of the facial recognition rollout despite clear relevance with the plan’s concerns.

“These revelations show yet again that the anti-racism commitments policing has undertaken via the equality initiative are failing to be integrated into wider practice. Our reports have warned that new technologies are being implemented in a landscape where racial disparities, weak scrutiny and poor data collection continue to exist.

“Any use of facial recognition must adhere to rigorous official guidelines, be independently scrutinised, and prove it diminishes rather than compounds ethnic bias.”

Official Statement

A government representative stated: “We takes the findings of the report with utmost gravity and we have implemented changes. A new algorithm has been independently tested and procured, 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 human involvement in each stage of the process and no arrest or charge would be taken without specialist personnel carefully reviewing the output.”