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Police forces across the UK successfully lobbied to deploy a facial recognition system acknowledged as discriminatory against females, young people, and members of minority ethnic backgrounds, following complaints that a less biased version generated a reduced number of investigative leads.

How the System Works

UK forces utilize the police national database (PND) to conduct searches using historical face recognition. This process entails comparing a reference photograph of a person of interest against a database of over 19 million mugshots to find possible hits.

Acknowledged Discrimination

The UK interior ministry admitted last week that the system was biased. This acknowledgment followed a study by the government's National Physical Laboratory found it incorrectly matched Black and Asian people and females at significantly higher rates than white men. The ministry stated it “had acted 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 disregarding fundamental rights.”

Known Issue

Official papers show that this discriminatory flaw has been recognized for more than a year. Furthermore, police forces argued to overturn an initial decision that was intended to mitigate the problem.

Police bosses were notified of the algorithmic discrimination in late 2024. The government-ordered laboratory study found the system was more likely to produce false positives for photos of females, Black people, and those under 40 years old.

A Reversed Decision

In response, the national police leadership body ordered that the accuracy setting required for possible hits be raised to a level where the bias was significantly reduced.

However, this decision was reversed the next month after forces complained that the modified technology was producing a lower number of “useful lines of inquiry”. NPCC documents indicate the stricter setting reduced the proportion of searches that yielded possible identifications from 56% to a mere under 15%.

Profound Inequalities

Although the authorities refused to say what setting is now in operation, the latest independent review discovered the system could generate false positives for women of Black heritage almost 100 times more often than for white women at specific configurations.

The ministry stated on these findings: “The testing identified that in a specific scenarios the software is more likely to wrongly flag some population segments in its search results.”

Balancing Utility and Fairness

Outlining the effect of the temporary raise to the system's accuracy setting, the police records state: “This adjustment significantly reduces the impact of bias across legally safeguarded attributes of ethnicity, generation and sex but had a substantially detrimental effect on operational effectiveness”. The documents add that police units argued that “a previously useful tool returned results of limited benefit”.

Wider Implementation Proposals

Meanwhile, the government has opened a two-and-a-half-month public review on its plans to widen the use of facial recognition technology. Policing minister Sarah Jones has labeled the tool as the “most significant advance since genetic fingerprinting”.

Expert and Oversight Concerns

Abimbola Johnson, head of the advisory panel for the national policing equality strategy, said: “There was very little consideration through equality strategy sessions of the facial recognition rollout even with obvious cross-over with the strategy's goals.

“These revelations demonstrate yet again that the pledges to combat discrimination the police has undertaken via the equality initiative are failing to be integrated into wider practice. Our reports have cautioned that innovative tools are being implemented in a landscape where ethnic inequalities, weak scrutiny and faulty information gathering already persist.

“All deployment of this technology must adhere to strict national standards, be independently scrutinised, and prove it diminishes rather than exacerbates ethnic bias.”

Official Statement

A government representative said: “The Home Office treat the findings of the study 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 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 further action would be taken without trained officers carefully reviewing the results.”