UK Law Enforcement Agencies Lobbied to Employ Discriminatory Face Scanning Technology

Law enforcement agencies across the United Kingdom effectively campaigned to deploy a facial recognition system acknowledged as biased against females, young people, and members of minority ethnic backgrounds, following complaints that a less biased version generated fewer potential suspects.

How the System Works

British police utilize the national police database to conduct searches using historical face recognition. This process entails comparing a reference photograph of a person of interest against a database of more than 19 million custody photos to find possible hits.

Acknowledged Discrimination

The Home Office conceded last week that the system was flawed. This acknowledgment followed a study by the government's National Physical Laboratory found it misidentified Black and Asian people and women at much greater frequency than Caucasian males. The Home Office said it “took steps on the findings”.

“This raises the issue of whether facial recognition only becomes effective if users accept discrimination in ethnicity and sex. Operational ease is a weak argument for overriding basic freedoms.”

Known Issue

Official papers reveal that this discriminatory flaw has been recognized for more than a year. Furthermore, police forces lobbied to reverse an earlier ruling that was designed to address the problem.

Senior officers were informed of the system's bias in late 2024. The Home Office-commissioned NPL review concluded the system was had a higher probability to suggest false positives for photos of females, Black people, and those aged 40 and under.

A Reversed Decision

In response, the National Police Chiefs’ Council (NPCC) mandated that the confidence threshold required for potential matches be raised to a level where the bias was greatly diminished.

However, this directive was reversed the next month after forces complained that the modified technology was generating a lower number of “useful lines of inquiry”. Internal records show the higher threshold reduced the number of searches that yielded possible identifications from over half to a just 14%.

Severe Disparities

Although the authorities refused to say what threshold is currently used, the latest NPL study discovered the system could produce false positives for Black women almost 100 times more often than for white women at certain settings.

The ministry stated on these results: “The testing identified 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

Describing the impact of the brief increase to the system's confidence threshold, the NPCC documents state: “The change greatly lessens the effect of bias across legally safeguarded attributes of ethnicity, age and gender but had a significant negative impact on police efficiency”. The papers add that forces complained that “a once effective tactic returned outcomes of limited benefit”.

Wider Implementation Proposals

Meanwhile, the government has opened a two-and-a-half-month 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 “most significant advance 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, commented: “There was scant discussion in race action plan meetings of the facial recognition rollout even with obvious cross-over with the plan’s concerns.

“These revelations show yet again that the pledges to combat discrimination policing has made via the race action plan are failing to be integrated into broader operations. Independent assessments have warned that new technologies are being implemented in a context where ethnic inequalities, inadequate oversight and poor data collection already persist.

“Any use of facial recognition must meet rigorous official guidelines, be subject to external review, and demonstrate it diminishes rather than exacerbates ethnic bias.”

Official Statement

A government representative said: “The Home Office takes the findings of the study seriously and we have already taken action. A new algorithm has been independently tested and acquired, which has demonstrated no measurable discrimination. It will be trialled early next year and will be subject to further assessment.

“The foremost aim is protecting the public. This gamechanging technology will support police to put criminals and rapists behind bars. There is officer review in each stage of the process and no arrest or charge would be pursued without specialist personnel carefully reviewing the output.”