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Law enforcement agencies across the United Kingdom successfully lobbied to use a facial recognition system acknowledged as biased against females, youths, and individuals from minority ethnic backgrounds, following complaints that a more accurate version generated fewer investigative leads.

The Technology in Practice

British police use the police national database (PND) to carry out searches using historical face recognition. This process entails matching a “probe image” of a suspect against a repository of more than 19 million custody photos to identify potential matches.

Acknowledged Discrimination

The UK interior ministry admitted last week that the system was flawed. This admission followed a review by the government's National Physical Laboratory determined it misidentified Black and Asian people and females at significantly higher rates than Caucasian males. The Home Office said it “had acted on the findings”.

“It prompts the question of whether facial recognition only becomes effective if users accept biases in race and gender. Operational ease is a poor argument for disregarding fundamental rights.”

Known Issue

Internal documents reveal that this bias has been recognized for more than a year. 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 late 2024. The Home Office-commissioned NPL review found the system was more likely to produce incorrect matches for photos of females, individuals of Black ethnicity, and those aged 40 and under.

A Reversed Decision

In reaction, the national police leadership body mandated that the confidence threshold required for potential matches be raised to a point where the disparity was greatly diminished.

However, this decision was overturned the next 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 that yielded possible identifications from over half to a just under 15%.

Severe Disparities

Although the authorities refused to say what setting is currently used, the latest NPL study found the system could produce false positives for Black women nearly a hundred times more often than for white women at specific configurations.

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

Operational Effectiveness vs. Bias

Outlining the effect of the temporary raise to the system's accuracy setting, the police records note: “This adjustment greatly lessens the impact of discrimination across legally safeguarded attributes of ethnicity, generation and sex but had a significant negative impact on operational effectiveness”. The papers further note that police units complained that “a once effective tactic returned outcomes of questionable value”.

Broader Rollout Plans

Meanwhile, the UK administration has opened a ten-week consultation on its proposals to expand the use of facial recognition technology. Policing minister Sarah Jones has labeled the tool as the “biggest breakthrough since DNA matching”.

Expert and Oversight Concerns

Abimbola Johnson, chair of the advisory panel for the police race action plan, said: “There was very little consideration through equality strategy sessions of the technology deployment despite obvious cross-over with the strategy's goals.

“These revelations show once again that the anti-racism commitments the police has made via 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 landscape where ethnic inequalities, weak scrutiny and faulty information gathering continue to exist.

“Any use of facial recognition must adhere to strict national standards, be subject to external review, and demonstrate it reduces rather than compounds racial disparity.”

Official Statement

A government representative said: “We takes the conclusions of the report with utmost gravity and we have implemented changes. A new algorithm has been externally evaluated and procured, which has demonstrated no measurable discrimination. It will be tested in the coming months and will be undergo evaluation.

“The foremost aim 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 process and no further action would be taken without trained officers carefully reviewing the output.”