British Law Enforcement Agencies Lobbied to Employ Discriminatory Facial Recognition Technology

Law enforcement agencies across the UK effectively campaigned to use a facial recognition system acknowledged as biased against women, youths, and members of ethnic minority groups, following complaints that a more accurate version produced a reduced number of potential suspects.

How the System Works

UK forces utilize the national police database to carry out retrospective facial recognition searches. This procedure involves matching a “probe image” of a person of interest against a repository of more than 19 million mugshots to identify possible hits.

Acknowledged Discrimination

The UK interior ministry admitted last week that the system was flawed. This admission followed a review by the National Physical Laboratory (NPL) found it misidentified Black and Asian people and women at much greater frequency than Caucasian males. The ministry stated it “had acted on the findings”.

“It prompts the question of whether this technology only becomes effective if users accept discrimination in race and gender. Convenience is a poor argument for disregarding fundamental rights.”

Known Issue

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

Senior officers were informed of the algorithmic discrimination in late 2024. The government-ordered NPL review found the system was more likely to produce incorrect matches for photos of females, individuals of Black ethnicity, and those under 40 years old.

A Reversed Decision

In response, the National Police Chiefs’ Council (NPCC) mandated that the confidence threshold required for possible hits be raised to a level where the bias was significantly reduced.

However, this decision was reversed the following month following complaints from police that the modified technology was producing fewer “investigative leads”. Internal records show the stricter setting reduced the proportion of queries resulting in potential matches from 56% to a mere under 15%.

Profound Inequalities

Although the authorities refused to say what setting is now in operation, the latest NPL study found the system could produce false positives for Black women almost 100 times more often than for white women at specific configurations.

The Home Office stated on these results: “Our evaluation identified 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 impact of the brief increase to the system's confidence threshold, the police records state: “The change significantly reduces the impact of bias across legally safeguarded attributes of ethnicity, age and sex but had a significant negative impact on operational effectiveness”. The papers add that forces complained that “a once effective tactic now delivered results of limited benefit”.

Broader Rollout Plans

Meanwhile, the government has opened a two-and-a-half-month consultation on its plans to widen the use of biometric scanning systems. Policing minister Sarah Jones has labeled the technology as the “biggest breakthrough since DNA matching”.

Criticism from Advisors and Monitors

The chair of a police oversight board, head of the independent scrutiny and oversight board for the police race action plan, said: “There was very little consideration through equality strategy sessions of the facial recognition rollout despite obvious cross-over with the strategy's goals.

“This disclosure show once again that the pledges to combat discrimination policing has undertaken through the equality initiative are not being translated into broader operations. Our reports have warned that new technologies are being rolled out in a context where racial disparities, inadequate oversight and faulty information gathering continue to exist.

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

Home Office Response

A Home Office spokesperson said: “We takes the conclusions of the report seriously and we have implemented changes. A updated software has been independently tested and procured, which has no statistically significant bias. It will be tested early next year and will be undergo further assessment.

“The foremost aim is ensuring public safety. This revolutionary tool will support police to put criminals and rapists behind bars. There is officer review in each stage of the process and no arrest or charge would be pursued without specialist personnel carefully reviewing the output.”