UK Law Enforcement Agencies Lobbied to Use Biased Face Scanning Technology

Law enforcement agencies across the UK successfully lobbied to use a facial recognition system acknowledged as discriminatory against women, young people, and members of ethnic minority groups, following complaints that a less biased version produced a reduced number of potential suspects.

The Technology in Practice

British police utilize the national police database to carry out searches using historical face recognition. This process entails matching a “probe image” of a person of interest against a repository of more than 19 million mugshots to find possible hits.

Acknowledged Discrimination

The Home Office admitted last week that the system was biased. This admission followed a review by the National Physical Laboratory (NPL) found it misidentified Black and Asian people and women at significantly higher rates than Caucasian males. The ministry stated it “had acted on the findings”.

“It prompts the issue of whether this technology only becomes useful if users tolerate discrimination in race and gender. Operational ease is a poor argument for overriding fundamental rights.”

Long-Standing Problem

Official papers show that this discriminatory flaw has been recognized for more than a year. Furthermore, law enforcement argued to overturn an initial decision that was designed to address the problem.

Senior officers were informed of the algorithmic discrimination in late 2024. The government-ordered NPL review concluded the system was more likely to suggest false positives for images depicting females, Black people, and those under 40 years old.

A Reversed Decision

In reaction, the National Police Chiefs’ Council (NPCC) ordered that the accuracy setting required for potential matches be increased to a level where the bias was significantly reduced.

However, this directive was overturned the following month following complaints from police that the modified technology was generating fewer “investigative leads”. NPCC documents show the higher threshold reduced the number of queries resulting in possible identifications from 56% to a just 14%.

Profound Inequalities

Although the Home Office and NPCC declined to specify what threshold is now in operation, the recent NPL study found the system could produce false positives for Black women almost 100 times more often than for white women at certain settings.

The Home Office commented on these results: “Our evaluation identified that in a specific scenarios the software is more likely to wrongly flag some population segments in its match reports.”

Balancing Utility and Fairness

Outlining the impact of the brief increase to the system's accuracy setting, the police records note: “This adjustment significantly reduces the effect of discrimination across legally safeguarded attributes of ethnicity, generation and gender but had a substantially detrimental effect on operational effectiveness”. The documents add that police units argued that “a once effective tactic now delivered outcomes of limited benefit”.

Wider Implementation Proposals

Meanwhile, the UK administration has launched a ten-week public review on its plans to widen the use of biometric scanning systems. Policing minister Sarah Jones has described the technology as the “most significant advance since genetic fingerprinting”.

Expert and Oversight Concerns

Abimbola Johnson, head of the advisory panel for the police race action plan, said: “There was scant discussion in equality strategy sessions of the technology deployment despite clear relevance with the plan’s concerns.

“This disclosure demonstrate once again that the pledges to combat discrimination policing has undertaken through the race action plan are failing to be integrated into broader operations. Independent assessments have warned that new technologies are being implemented in a landscape where racial disparities, inadequate oversight and poor data collection already persist.

“Any use of facial recognition must meet rigorous official guidelines, be independently scrutinised, and demonstrate it reduces rather than exacerbates racial disparity.”

Home Office Response

A Home Office spokesperson stated: “The Home Office takes the findings of the study with utmost gravity and we have already taken action. 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 protecting the public. This revolutionary tool will support police to put criminals and rapists behind bars. There is human involvement in every step of the procedure and no further action would be pursued without trained officers carefully reviewing the output.”