British Law Enforcement Agencies Campaign to Employ Discriminatory Face Scanning Technology

Law enforcement agencies across the United Kingdom effectively campaigned to deploy a facial recognition system known to be biased against females, youths, and individuals from ethnic minority groups, following complaints that a less biased version produced fewer investigative leads.

The Technology in Practice

British police utilize the national police database to carry out searches using historical face recognition. This process involves matching a “probe image” of a person of interest against a repository of more than 19 million mugshots to find potential matches.

Admitted Bias

The Home Office conceded last week that the technology was biased. This admission came after a review by the National Physical Laboratory (NPL) determined it misidentified people of Black and Asian heritage and women at much greater frequency than Caucasian males. The ministry stated it “had acted on the findings”.

“It prompts the issue of whether this technology only becomes useful if users accept discrimination in race and sex. Convenience is a poor argument for disregarding basic freedoms.”

Long-Standing Problem

Internal documents reveal that this bias has been known about for over twelve months. Furthermore, police forces argued to overturn an initial decision that was intended to mitigate the problem.

Police bosses were notified of the system's bias in late 2024. The Home Office-commissioned NPL review concluded the system was had a higher probability to suggest false positives for photos of females, individuals of Black ethnicity, and those under 40 years old.

A Reversed Decision

In reaction, the National Police Chiefs’ Council (NPCC) mandated that the accuracy setting required for possible hits be raised to a point where the disparity was greatly diminished.

However, this directive was overturned the next month after forces complained that the modified technology was generating a lower number of “useful lines of inquiry”. NPCC documents show the higher threshold reduced the proportion of searches resulting in possible identifications from 56% to a just 14%.

Severe Disparities

Although the authorities declined to specify what setting is currently used, the latest independent review found the system could produce false positives for women of Black heritage almost 100 times more frequently than for Caucasian women at specific configurations.

The Home Office commented on these results: “The testing found that in a specific scenarios the software is more likely to incorrectly include some population segments in its search results.”

Operational Effectiveness vs. Bias

Outlining the effect of the temporary raise to the system's confidence threshold, the NPCC documents note: “The change greatly lessens the effect of discrimination across legally safeguarded attributes of race, 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”.

Broader Rollout Plans

Meanwhile, the government has launched a ten-week consultation on its plans to expand the use of facial recognition technology. Policing minister Sarah Jones has described the tool as the “biggest breakthrough since DNA matching”.

Expert and Oversight Concerns

The chair of a police oversight board, chair of the independent scrutiny and oversight board for the national policing equality strategy, commented: “There was scant discussion through equality strategy sessions of the facial recognition rollout despite clear relevance with the plan’s concerns.

“These revelations demonstrate once again that the pledges to combat discrimination the police has undertaken via the equality initiative are failing to be integrated into broader operations. Our reports have warned that innovative tools are being implemented in a context where racial disparities, weak scrutiny and poor data collection already persist.

“Any use of facial recognition must adhere to rigorous official guidelines, be independently scrutinised, and demonstrate it reduces rather than compounds ethnic bias.”

Home Office Response

A Home Office spokesperson stated: “We takes the conclusions of the report with utmost gravity and we have already taken action. A updated software has been externally evaluated and procured, which has no statistically significant bias. 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 assist officers to put criminals and rapists behind bars. There is officer review in each stage of the procedure and no further action would be taken without specialist personnel carefully reviewing the results.”