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Law enforcement agencies across the United Kingdom successfully lobbied to use a facial recognition system known to be biased against females, young people, and members of ethnic minority groups, after complaining that a more accurate version generated a reduced number of investigative leads.

The Technology in Practice

British police use the national police database to conduct retrospective facial recognition searches. This procedure entails matching a reference photograph of a person of interest against a database of more than 19 million custody photos to find potential matches.

Acknowledged Discrimination

The UK interior ministry conceded last week that the system was flawed. This acknowledgment came after a review by the government's National Physical Laboratory found it incorrectly matched people of Black and Asian heritage and females at much greater frequency than white men. The Home Office stated it “took steps on the findings”.

“This raises the question of whether this technology only becomes effective if users tolerate discrimination in ethnicity 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 over twelve months. Furthermore, law enforcement argued to overturn an earlier ruling that was designed to mitigate the problem.

Police bosses were informed of the algorithmic discrimination in September 2024. The Home Office-commissioned NPL review concluded the system was had a higher probability to suggest false positives 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 accuracy setting required for potential matches be increased to a point where the disparity was greatly diminished.

However, this directive was overturned the next month after forces complained that the adjusted system was generating a lower number of “useful lines of inquiry”. NPCC documents show the higher threshold cut the proportion of queries resulting in potential matches from over half 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 discovered the system could produce false positives for women of Black heritage nearly a hundred times more often than for Caucasian women at certain settings.

The Home Office stated on these findings: “The testing identified that in a limited set of circumstances the software is has a greater tendency to wrongly flag some demographic groups in its match reports.”

Operational Effectiveness vs. Bias

Outlining the impact of the brief increase to the system's accuracy setting, the police records note: “The change greatly lessens the effect of bias across protected characteristics of ethnicity, generation and sex but had a significant negative impact on police efficiency”. The papers further note that forces complained that “a once effective tactic now delivered outcomes of questionable value”.

Wider Implementation Proposals

Meanwhile, the UK administration has opened a two-and-a-half-month consultation on its plans to expand the use of biometric scanning systems. The minister for police Sarah Jones has labeled the tool as the “biggest breakthrough since genetic fingerprinting”.

Expert and Oversight Concerns

Abimbola Johnson, chair of the advisory panel for the national policing equality strategy, commented: “There was scant consideration in equality strategy sessions of the facial recognition rollout 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 race action plan are failing to be integrated into broader operations. Independent assessments have warned that innovative tools are being rolled out in a context where racial disparities, weak scrutiny and poor data collection continue to exist.

“All deployment of facial recognition must meet rigorous official guidelines, be independently scrutinised, and prove it reduces rather than exacerbates racial disparity.”

Official Statement

A government representative stated: “We takes the findings 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 undergo evaluation.

“The foremost aim is ensuring public safety. This gamechanging technology will assist officers to apprehend and prosecute offenders. There is officer review in every step of the procedure and no further action would be pursued without trained officers carefully reviewing the results.”