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Police forces across the United Kingdom successfully lobbied to deploy a face scanning system known to be biased 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

British police utilize the police national database (PND) to carry out retrospective facial recognition searches. This procedure involves matching a reference photograph of a suspect against a repository of over 19 million mugshots to find possible hits.

Admitted Bias

The UK interior ministry conceded last week that the technology was flawed. This admission followed a review by the National Physical Laboratory (NPL) found it incorrectly matched people of Black and Asian heritage and women at much greater frequency than Caucasian males. The Home Office said it “had acted on the findings”.

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

Known Issue

Internal documents show that this bias has been recognized for over twelve months. Furthermore, law enforcement lobbied to reverse an initial decision that was designed to address the problem.

Police bosses were informed of the system's bias in late 2024. The government-ordered laboratory study concluded the system was had a higher probability to suggest false positives for images depicting females, Black people, and those aged 40 and under.

A Policy U-Turn

In response, the National Police Chiefs’ Council (NPCC) ordered that the accuracy setting required for potential matches be raised to a level where the disparity was greatly diminished.

However, this decision was reversed the following month following complaints from police that the adjusted system was producing fewer “investigative leads”. Internal records indicate the higher threshold cut the number of queries resulting in possible identifications from 56% to a just 14%.

Profound Inequalities

Although the Home Office and NPCC declined to specify what setting is now in operation, the latest NPL study found the system could generate incorrect matches for Black women nearly a hundred times more often than for white women at certain settings.

The Home Office stated on these findings: “Our evaluation identified that in a specific scenarios the algorithm is more likely to wrongly flag some demographic groups in its search results.”

Operational Effectiveness vs. Bias

Outlining the effect of the brief increase to the system's accuracy setting, the NPCC documents note: “This adjustment significantly reduces the impact of bias across protected characteristics of ethnicity, age and sex but had a substantially detrimental effect on operational effectiveness”. The documents further note that forces complained that “a previously useful tool returned results of limited benefit”.

Broader Rollout Plans

Meanwhile, the UK administration has launched a ten-week consultation on its plans to widen the use of facial recognition technology. Policing minister the relevant minister has labeled the technology as the “most significant advance since genetic fingerprinting”.

Expert and Oversight Concerns

Abimbola Johnson, head of the advisory panel for the police race action plan, said: “There was scant discussion in equality strategy sessions of the technology deployment even with obvious cross-over with the strategy's goals.

“These revelations show yet again that the pledges to combat discrimination policing has made through the race action plan are failing to be integrated into broader operations. Our reports 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 prove it reduces rather than compounds racial disparity.”

Official Statement

A government representative stated: “We takes the conclusions of the report seriously and we have already taken action. A updated software has been independently tested 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 revolutionary tool will assist police to apprehend and prosecute offenders. There is officer review in each stage of the procedure and no further action would be pursued without trained officers carefully reviewing the results.”