🔗 Share this article

Police forces across the United Kingdom successfully lobbied to deploy 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 produced a reduced number of investigative leads.

The Technology in Practice

UK forces utilize the national police database to conduct searches using historical face recognition. This process involves comparing a “probe image” of a suspect against a repository of over 19 million custody photos to identify possible hits.

Admitted Bias

The UK interior ministry admitted last week that the technology was flawed. This acknowledgment came after a study by the government's National Physical Laboratory found it incorrectly matched Black and Asian people and females at significantly higher rates than white men. The Home Office stated it “had acted on the findings”.

“It prompts the issue of whether this technology only becomes useful if users accept biases in race and sex. Operational ease is a weak argument for overriding basic freedoms.”

Known Issue

Official papers show that this discriminatory flaw has been recognized for over twelve months. Furthermore, law enforcement lobbied to reverse an earlier ruling that was designed to address the problem.

Police bosses were notified of the algorithmic discrimination in late 2024. The government-ordered laboratory study found the system was had a higher probability to produce incorrect matches for photos of women, Black people, and those under 40 years old.

A Policy U-Turn

In reaction, the national police leadership body ordered that the accuracy setting required for potential matches be raised to a point where the bias was significantly reduced.

However, this directive was overturned the next month after forces complained that the adjusted system was generating a lower number of “investigative leads”. Internal records show the stricter setting reduced the proportion of searches resulting in possible identifications from 56% to a mere 14%.

Profound Inequalities

Although the authorities declined to specify what setting is now in operation, the recent NPL study found the system could generate incorrect matches for women of Black heritage almost 100 times more frequently than for white women at specific configurations.

The Home Office commented on these findings: “Our evaluation found that in a limited set of circumstances the software is more likely to wrongly flag some demographic groups in its search results.”

Balancing Utility and Fairness

Outlining the effect of the temporary raise to the system's confidence threshold, the NPCC documents state: “The change greatly lessens the impact of bias across legally safeguarded attributes of ethnicity, generation and gender but had a substantially detrimental effect on police efficiency”. The papers further note that police units complained that “a once effective tactic returned outcomes of questionable value”.

Wider Implementation Proposals

Meanwhile, the UK administration has opened 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 technology as the “most significant advance since genetic fingerprinting”.

Criticism from Advisors and Monitors

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

“These revelations demonstrate once again that the pledges to combat discrimination policing has made through the race action plan are failing to be integrated into wider practice. Independent assessments have warned that new technologies are being rolled out in a landscape where ethnic inequalities, inadequate oversight and poor data collection already persist.

“All deployment of facial recognition 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 conclusions 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 support officers to apprehend and prosecute offenders. There is human involvement in every step of the process and no further action would be taken without specialist personnel carefully reviewing the results.”