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Law enforcement agencies across the United Kingdom successfully lobbied to deploy a facial recognition system known to be discriminatory against females, young people, and individuals from minority ethnic backgrounds, following complaints that a less biased version generated fewer investigative leads.

The Technology in Practice

UK forces utilize the police national database (PND) to conduct retrospective facial recognition searches. This procedure entails comparing a reference photograph of a suspect against a repository of more than 19 million mugshots to find possible hits.

Acknowledged Discrimination

The Home Office admitted last week that the technology was biased. This admission followed a review by the government's National Physical Laboratory found it misidentified people of Black and Asian heritage and females at much greater frequency than white men. The ministry said it “took steps on the findings”.

“This raises the issue of whether facial recognition only becomes useful if users tolerate biases in race and sex. Operational ease is a weak argument for overriding basic freedoms.”

Known Issue

Internal documents 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 address the problem.

Senior officers were notified of the algorithmic discrimination in September 2024. The government-ordered laboratory study found the system was had a higher probability to suggest incorrect matches for photos of females, individuals of Black ethnicity, and those under 40 years old.

A Reversed Decision

In reaction, the national police leadership body mandated that the accuracy setting required for possible hits be raised 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 producing fewer “investigative leads”. Internal records show the stricter setting cut the proportion of queries that yielded potential matches from 56% to a just 14%.

Severe Disparities

Although the Home Office and NPCC declined to specify what setting is now in operation, the recent independent review 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 more likely to wrongly flag some demographic groups in its match reports.”

Operational Effectiveness vs. Bias

Outlining the effect of the brief increase to the system's accuracy setting, the police records note: “The change significantly reduces the impact of discrimination across protected characteristics of race, age and sex but had a substantially detrimental effect on police efficiency”. The papers further note that police units argued that “a previously useful tool returned results of limited benefit”.

Wider Implementation Proposals

Meanwhile, the UK administration has launched a two-and-a-half-month public review on its plans to expand the use of facial recognition technology. The minister for police the relevant minister has labeled the technology as the “most significant advance since genetic fingerprinting”.

Criticism from Advisors and Monitors

Abimbola Johnson, chair of the advisory panel for the national policing equality strategy, commented: “There was scant discussion in race action plan meetings of the technology deployment even with clear relevance with the plan’s concerns.

“These revelations demonstrate yet again that the anti-racism commitments the police has undertaken via the race action plan are not being translated into broader operations. Independent assessments have cautioned that new technologies are being rolled out in a landscape where racial disparities, inadequate oversight and faulty information gathering continue to exist.

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

Home Office Response

A government representative stated: “We treat the conclusions of the report seriously and we have already taken action. A updated software has been externally evaluated and acquired, which has no statistically significant bias. It will be tested early next year and will be undergo evaluation.

“The foremost aim is ensuring public safety. This gamechanging technology will support police to apprehend and prosecute offenders. There is officer review in each stage of the process and no further action would be taken without specialist personnel carefully reviewing the results.”