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Police forces across the United Kingdom effectively campaigned to deploy a facial recognition system acknowledged as discriminatory against females, youths, and members of ethnic minority groups, after complaining that a less biased version generated a reduced number of investigative leads.

The Technology in Practice

British police utilize the police national database (PND) to carry out searches using historical face recognition. This procedure entails comparing a reference photograph of a person of interest against a repository 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 came after a study by the government's National Physical Laboratory found it incorrectly matched 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 facial recognition only becomes effective if users tolerate discrimination in race and gender. Operational ease is a poor argument for disregarding fundamental rights.”

Known Issue

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

Police bosses were informed of the system's bias in September 2024. The government-ordered NPL review concluded the system was more likely to produce incorrect matches for images depicting females, individuals of Black ethnicity, and those aged 40 and under.

A Policy U-Turn

In reaction, the National Police Chiefs’ Council (NPCC) ordered that the confidence threshold required for possible hits be raised to a point where the disparity was significantly reduced.

However, this directive was overturned the following month following complaints from police that the modified technology was producing a lower number of “useful lines of inquiry”. NPCC documents show the stricter setting cut the number of queries that yielded possible identifications from over half to a just 14%.

Severe Disparities

Although the Home Office and NPCC declined to specify what threshold is now in operation, the recent independent review discovered the system could produce false positives for Black women almost 100 times more frequently than for Caucasian women at specific configurations.

The ministry commented on these findings: “Our evaluation identified that in a specific scenarios the software is has a greater tendency to wrongly flag some population segments in its match reports.”

Operational Effectiveness vs. Bias

Outlining the effect of the brief increase to the system's confidence threshold, the police records state: “The change significantly reduces the effect of discrimination across legally safeguarded attributes of race, age and sex but had a substantially detrimental effect on operational effectiveness”. The documents add that forces complained that “a previously useful tool now delivered results of questionable value”.

Wider Implementation Proposals

Meanwhile, the government has launched a two-and-a-half-month consultation on its proposals to widen the use of biometric scanning systems. Policing minister the relevant minister has described the technology as the “most significant advance since genetic fingerprinting”.

Criticism from Advisors and Monitors

Abimbola Johnson, chair of the independent scrutiny and oversight board for the national policing equality strategy, commented: “There was scant consideration through equality strategy sessions of the technology deployment even with clear relevance with the strategy's goals.

“These revelations show once again that the anti-racism commitments policing has undertaken through the race action plan are not being translated into wider practice. Our reports have cautioned that innovative tools are being implemented in a context where racial disparities, inadequate oversight and poor data collection continue to exist.

“Any use of this technology must adhere to strict national standards, be subject to external review, and prove it diminishes rather than compounds ethnic bias.”

Official Statement

A government representative said: “We takes the conclusions of the report with utmost gravity and we have already taken action. A updated software has been independently tested and procured, which has no statistically significant bias. It will be trialled early next year and will be undergo further assessment.

“Our priority is protecting the public. This gamechanging technology 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 carefully reviewing the results.”