🔗 Share this article

Law enforcement agencies across the United Kingdom successfully lobbied to deploy a face scanning system known to be discriminatory against women, youths, and individuals from ethnic minority groups, following complaints that a more accurate version produced fewer investigative leads.

The Technology in Practice

UK forces utilize the national police database to carry out searches using historical face recognition. This procedure involves comparing a “probe image” of a person of interest against a database of over 19 million mugshots to identify potential matches.

Admitted Bias

The UK interior ministry admitted last week that the system was flawed. This acknowledgment came after a review by the government's National Physical Laboratory determined it misidentified people of Black and Asian heritage and women at significantly higher rates than white men. The ministry stated it “took steps on the findings”.

“It prompts the issue of whether facial recognition only becomes useful if users tolerate discrimination in ethnicity and sex. Operational ease is a poor argument for overriding fundamental rights.”

Long-Standing Problem

Internal documents show that this discriminatory flaw has been known about for over twelve months. Furthermore, police forces argued to overturn an initial decision that was designed to address the problem.

Senior officers were notified of the system's bias in late 2024. The Home Office-commissioned laboratory study found the system was more likely to suggest false positives for photos of females, Black people, and those aged 40 and under.

A Reversed Decision

In response, the national police leadership body mandated that the accuracy setting required for possible hits be raised to a level where the bias was greatly diminished.

However, this decision was overturned the following month following complaints from police that the modified technology was producing fewer “investigative leads”. NPCC documents show the stricter setting cut the proportion of searches resulting in potential matches from over half to a mere 14%.

Profound Inequalities

Although the authorities refused to say what setting is now in operation, the recent independent review found the system could produce false positives for women of Black heritage nearly a hundred times more often than for Caucasian women at specific configurations.

The ministry commented on these findings: “The testing found that in a specific scenarios the software is has a greater tendency to wrongly flag some demographic groups in its search results.”

Balancing Utility and Fairness

Outlining the effect of the brief increase to the system's accuracy setting, the NPCC documents state: “The change greatly lessens the impact of discrimination across protected characteristics of ethnicity, generation and gender but had a significant negative impact on police efficiency”. The documents add that police units argued that “a once effective tactic now delivered results of questionable value”.

Broader Rollout Plans

Meanwhile, the UK administration has launched a ten-week consultation on its proposals to widen the use of biometric scanning systems. The minister for police the relevant minister has described the tool as the “biggest breakthrough since genetic fingerprinting”.

Criticism from Advisors and Monitors

The chair of a police oversight board, chair of the advisory panel for the national policing equality strategy, said: “We observed very little consideration in race action plan meetings of the facial recognition rollout despite clear relevance with the plan’s concerns.

“These revelations demonstrate once again that the anti-racism commitments the police has made via the equality initiative are failing to be integrated into broader operations. Our reports have cautioned that new technologies are being implemented in a context where racial disparities, inadequate oversight and faulty information gathering continue to exist.

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

Home Office Response

A government representative stated: “We treat the findings of the study seriously and we have already taken action. A updated software has been externally evaluated and acquired, which has demonstrated no measurable discrimination. It will be tested early next year and will be subject to evaluation.

“The foremost aim is ensuring public safety. This gamechanging technology will assist 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 output.”