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Law enforcement agencies across the United Kingdom effectively campaigned to use a facial recognition system known to be biased against females, youths, and individuals from minority ethnic backgrounds, after complaining that a less biased version produced a reduced number of investigative leads.

How the System Works

UK forces utilize the national police database to carry out searches using historical face recognition. This process involves matching a “probe image” of a suspect against a database of over 19 million custody photos to identify possible hits.

Admitted Bias

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

“This raises the issue of whether facial recognition only becomes effective if users accept biases in race and gender. Operational ease is a poor argument for overriding fundamental rights.”

Long-Standing Problem

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

Senior officers were informed of the algorithmic discrimination in late 2024. The government-ordered laboratory study concluded the system was had a higher probability to suggest false positives for photos of women, Black people, and those under 40 years old.

A Policy U-Turn

In response, the national police leadership body ordered that the accuracy setting required for potential matches be increased to a level where the disparity was greatly diminished.

However, this decision was overturned the next month following complaints from police that the adjusted system was generating a lower number of “useful lines of inquiry”. Internal records indicate the stricter setting reduced the number of queries that yielded potential matches from 56% to a just 14%.

Profound Inequalities

Although the authorities refused to say what threshold is currently used, the recent independent review discovered the system could generate false positives for Black women nearly a hundred times more often than for white women at certain settings.

The Home Office commented on these findings: “The testing identified that in a limited set of circumstances the algorithm is more likely 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 confidence threshold, the NPCC documents note: “This adjustment significantly reduces the impact of discrimination across legally safeguarded attributes of ethnicity, age and gender 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 government has opened a ten-week 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 DNA matching”.

Expert and Oversight Concerns

Abimbola Johnson, chair of the independent scrutiny and oversight board for the national policing equality strategy, commented: “There was very little discussion in race action plan meetings of the technology deployment despite obvious cross-over with the plan’s concerns.

“This disclosure demonstrate yet again that the pledges to combat discrimination policing has made through the race action plan are failing to be integrated into wider practice. Our reports have cautioned that innovative tools are being rolled out in a landscape where ethnic inequalities, weak scrutiny and poor data collection continue to exist.

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

Official Statement

A government representative said: “We treat the conclusions of the report with utmost gravity and we have already taken action. A updated software has been externally evaluated and acquired, which has demonstrated no measurable discrimination. It will be trialled in the coming months and will be subject to further assessment.

“Our priority is protecting the public. This gamechanging technology will support officers to apprehend and prosecute offenders. There is officer review in every step of the process and no arrest or charge would be pursued without trained officers carefully reviewing the results.”