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Law enforcement agencies across the United Kingdom successfully lobbied to deploy a face scanning system acknowledged as discriminatory against women, young people, and members of ethnic minority groups, after complaining that a less biased version produced fewer investigative leads.

The Technology in Practice

British police use the national police database to conduct retrospective facial recognition searches. This procedure involves matching a reference photograph of a person of interest against a repository of over 19 million custody photos to find possible hits.

Acknowledged Discrimination

The Home Office admitted last week that the system was flawed. This admission followed a study by the government's National Physical Laboratory determined it misidentified people of Black and Asian heritage and women at significantly higher rates than white men. The ministry stated it “had acted on the findings”.

“This raises the issue of whether this technology only becomes effective if users accept discrimination in ethnicity and gender. Convenience is a weak argument for overriding basic freedoms.”

Known Issue

Official papers reveal that this discriminatory flaw has been known about for over twelve months. Furthermore, police forces argued to overturn an initial decision that was designed to mitigate the problem.

Police bosses were notified of the system's bias in late 2024. The Home Office-commissioned NPL review found the system was more likely to suggest false positives for images depicting women, individuals of Black ethnicity, and those aged 40 and under.

A Policy U-Turn

In reaction, the National Police Chiefs’ Council (NPCC) mandated that the accuracy setting required for potential matches be increased to a point where the bias was greatly diminished.

However, this decision was overturned the following month after forces complained that the modified technology was generating fewer “useful lines of inquiry”. NPCC documents show the higher threshold reduced the number of queries resulting in possible identifications from 56% to a mere under 15%.

Severe Disparities

Although the Home Office and NPCC refused to say what setting is currently used, the latest independent review discovered the system could generate incorrect matches for Black women nearly a hundred times more often than for white women at specific configurations.

The Home Office commented on these results: “Our evaluation found that in a specific scenarios the software is has a greater tendency to wrongly flag some demographic groups in its match reports.”

Balancing Utility and Fairness

Outlining the impact of the temporary raise to the system's accuracy setting, the NPCC documents state: “This adjustment greatly lessens the effect of discrimination across legally safeguarded attributes of race, generation and gender but had a substantially detrimental effect on operational effectiveness”. The documents add that police units complained that “a previously useful tool now delivered results of questionable value”.

Broader Rollout Plans

Meanwhile, the government has launched a ten-week consultation on its proposals to expand the use of facial recognition technology. The minister for police the relevant minister has labeled the tool as the “biggest breakthrough since genetic fingerprinting”.

Expert and Oversight Concerns

Abimbola Johnson, chair of the advisory panel for the police race action plan, said: “We observed scant consideration through equality strategy sessions of the facial recognition rollout despite obvious cross-over with the plan’s concerns.

“These revelations demonstrate yet again that the pledges to combat discrimination the police has made through the race action plan are not being translated into wider practice. Our reports have cautioned that innovative tools are being implemented in a landscape where racial disparities, weak scrutiny and faulty information gathering continue to exist.

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

Official Statement

A Home Office spokesperson stated: “The Home Office treat the conclusions of the report seriously and we have already taken action. A updated software has been externally evaluated and procured, which has no statistically significant bias. It will be tested in the coming months and will be subject to further assessment.

“The foremost aim is protecting the public. This revolutionary tool will support officers to apprehend and prosecute offenders. There is officer review in each stage of the process and no arrest or charge would be pursued without trained officers meticulously examining the results.”