🔗 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 minority ethnic backgrounds, after complaining that a less biased version generated fewer investigative leads.

How the System Works

UK forces use the national police database to conduct retrospective facial recognition searches. This process entails comparing a “probe image” of a suspect against a repository of over 19 million custody photos to find possible hits.

Acknowledged Discrimination

The UK interior ministry admitted last week that the system was biased. This admission followed a review by the National Physical Laboratory (NPL) determined it misidentified people of Black and Asian heritage and females at significantly higher rates than white men. The Home Office stated it “took steps on the findings”.

“It prompts the issue of whether this technology only becomes useful if users tolerate discrimination in race and sex. Operational ease is a poor argument for disregarding basic freedoms.”

Long-Standing Problem

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

Police bosses were notified of the algorithmic discrimination in September 2024. The government-ordered laboratory study concluded the system was had a higher probability to suggest incorrect matches 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 potential matches be increased to a level where the disparity was greatly diminished.

However, this directive was overturned the following month after forces complained that the modified technology was producing fewer “useful lines of inquiry”. NPCC documents show the higher threshold cut the number of queries resulting in possible identifications from 56% to a just 14%.

Severe Disparities

Although the authorities declined to specify what threshold is now in operation, the recent independent review discovered the system could produce incorrect matches for women of Black heritage nearly a hundred times more frequently than for white women at certain settings.

The ministry stated on these findings: “The testing found that in a limited set of circumstances the software is has a greater tendency to incorrectly include some demographic groups in its search results.”

Balancing Utility and Fairness

Describing the effect of the brief increase to the system's accuracy setting, the NPCC documents state: “This adjustment significantly reduces the effect of bias across legally safeguarded attributes 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 returned results of questionable value”.

Wider Implementation Proposals

Meanwhile, the UK administration has opened a two-and-a-half-month consultation on its plans to expand the use of facial recognition technology. Policing minister the relevant minister has labeled the tool as the “most significant advance since DNA matching”.

Expert and Oversight Concerns

Abimbola Johnson, chair of the independent scrutiny and oversight board for the national policing equality strategy, commented: “We observed scant consideration through equality strategy sessions of the facial recognition rollout even with clear relevance with the strategy's goals.

“This disclosure demonstrate yet again that the anti-racism commitments policing has made via the equality initiative are not being translated into broader operations. Independent assessments have warned that new technologies are being implemented in a landscape where racial disparities, inadequate oversight and faulty information gathering already persist.

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

Official Statement

A Home Office spokesperson said: “We takes the conclusions of the study with utmost gravity and we have already taken action. A new algorithm has been externally evaluated and procured, which has no statistically significant bias. It will be tested in the coming months and will be undergo evaluation.

“Our priority is ensuring public safety. This gamechanging technology will assist officers to put criminals and rapists behind bars. There is officer review in every step of the process and no arrest or charge would be pursued without trained officers carefully reviewing the results.”