UK Law Enforcement Agencies Campaign to Employ Discriminatory Facial Recognition Technology

Police forces across the United Kingdom effectively campaigned to use a face scanning system known to be discriminatory against women, young people, and individuals from minority ethnic backgrounds, following complaints that a more accurate version generated fewer investigative leads.

How the System Works

British police use the police national database (PND) to conduct searches using historical face recognition. This process involves matching a reference photograph of a suspect against a database 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 National Physical Laboratory (NPL) found it incorrectly matched Black and Asian people and females at significantly higher rates than white men. The ministry said it “took steps on the findings”.

“This raises the question of whether this technology only becomes effective if users accept biases in race and gender. Operational ease is a weak argument for overriding fundamental rights.”

Long-Standing Problem

Internal documents show that this bias has been recognized for more than a year. Furthermore, law enforcement lobbied to reverse an earlier ruling that was designed to address the problem.

Police bosses were notified of the system's bias in September 2024. The government-ordered NPL review found the system was had a higher probability to produce 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) mandated that the accuracy setting required for possible hits be increased to a point where the disparity was significantly reduced.

However, this directive was reversed the following month after forces complained that the adjusted system was producing a lower number of “investigative leads”. NPCC documents show the stricter setting cut the number of searches resulting in possible identifications from 56% to a just under 15%.

Severe Disparities

Although the authorities refused to say what setting is now in operation, the latest independent review found the system could generate incorrect matches for Black women nearly a hundred times more frequently than for white women at certain settings.

The Home Office stated on these results: “The testing found that in a specific scenarios the software is has a greater tendency to wrongly flag some demographic groups in its search results.”

Operational Effectiveness vs. Bias

Describing the effect of the temporary raise to the system's accuracy setting, the NPCC documents state: “This adjustment greatly lessens the impact of discrimination across protected characteristics of ethnicity, age and sex but had a significant negative impact on police efficiency”. The documents further note that forces argued that “a once effective tactic returned outcomes of questionable value”.

Wider Implementation Proposals

Meanwhile, the UK administration has opened a two-and-a-half-month consultation on its proposals 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: “We observed scant discussion through race action plan meetings of the facial recognition rollout despite clear relevance 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 not being translated into broader operations. Our reports have warned that new technologies are being implemented in a landscape where ethnic inequalities, weak scrutiny and poor data collection already persist.

“Any use of this technology must adhere to strict national standards, be subject to external review, and prove it reduces rather than compounds ethnic bias.”

Official Statement

A Home Office spokesperson said: “We treat the findings of the report with utmost gravity and we have already taken action. A new algorithm has been externally evaluated and acquired, which has demonstrated no measurable discrimination. It will be tested in the coming months and will be subject to further assessment.

“Our priority is ensuring public safety. This revolutionary tool will support officers to put criminals and rapists behind bars. There is officer review in every step of the process and no further action would be pursued without trained officers meticulously examining the results.”