UK Law Enforcement Agencies Lobbied to Employ Biased Facial Recognition Systems

Police forces across the UK successfully lobbied to use a facial recognition system known to be discriminatory against women, youths, and individuals from minority ethnic backgrounds, after complaining that a more accurate version produced fewer potential suspects.

The Technology in Practice

British police use the police national database (PND) to conduct searches using historical face recognition. This procedure entails matching a reference photograph of a suspect against a database of over 19 million mugshots to identify potential matches.

Acknowledged Discrimination

The Home Office 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 Caucasian males. The Home Office stated it “took steps on the findings”.

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

Long-Standing Problem

Official papers reveal that this bias has been recognized for over twelve months. Furthermore, law enforcement argued to overturn an earlier ruling that was designed to mitigate the problem.

Senior officers were informed of the algorithmic discrimination in late 2024. The government-ordered laboratory study found the system was more likely to produce incorrect matches for photos of women, 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 decision was reversed the next month after forces complained that the modified technology was producing a lower number of “investigative leads”. NPCC documents show the higher threshold cut the number of queries resulting in possible identifications from over half to a just 14%.

Profound Inequalities

Although the authorities refused to say what setting is now in operation, the recent independent review discovered the system could produce incorrect matches for women of Black heritage almost 100 times more frequently than for white women at specific configurations.

The ministry stated on these findings: “Our evaluation found that in a limited set of circumstances the algorithm is more likely to wrongly flag some population segments in its match reports.”

Balancing Utility and Fairness

Outlining the impact of the temporary raise to the system's confidence threshold, the NPCC documents state: “The change greatly lessens the impact of discrimination across protected characteristics of race, generation and gender but had a significant negative impact on operational effectiveness”. The papers further note that forces complained that “a previously useful tool now delivered results of limited benefit”.

Wider Implementation Proposals

Meanwhile, the government has opened a ten-week consultation on its proposals to widen the use of facial recognition technology. Policing minister Sarah Jones has labeled the tool as the “biggest breakthrough since genetic fingerprinting”.

Criticism from Advisors and Monitors

Abimbola Johnson, head of the independent scrutiny and oversight board for the national policing equality strategy, said: “There was very little discussion in equality strategy sessions of the technology deployment even with clear relevance with the plan’s concerns.

“These revelations show once again that the pledges to combat discrimination policing has made through the equality initiative are failing to be integrated into broader operations. Independent assessments have warned that new technologies are being rolled out in a landscape where racial disparities, inadequate oversight and faulty information gathering already persist.

“All deployment of this technology must meet strict national standards, be independently scrutinised, and demonstrate it reduces rather than compounds ethnic bias.”

Home Office Response

A Home Office spokesperson stated: “The Home Office treat the conclusions of the study with utmost gravity and we have implemented changes. A updated software has been independently tested and procured, which has demonstrated no measurable discrimination. It will be tested in the coming months and will be undergo evaluation.

“Our priority 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 arrest or charge would be pursued without specialist personnel meticulously examining the results.”