UK Police Forces Campaign to Employ Discriminatory Face Scanning Technology

Law enforcement agencies across the United Kingdom effectively campaigned to deploy a face scanning system known to be discriminatory against females, youths, and members of ethnic minority groups, after complaining that a less biased version produced a reduced number of potential suspects.

How the System Works

UK forces utilize the national police database to conduct searches using historical face recognition. This procedure entails matching a reference photograph of a suspect against a database of more than 19 million mugshots to find possible hits.

Acknowledged Discrimination

The UK interior ministry admitted last week that the technology was biased. This admission came after a study by the government's National Physical Laboratory found it incorrectly matched Black and Asian people and women at significantly higher rates than Caucasian males. The ministry said it “had acted on the findings”.

“This raises the question of whether facial recognition only becomes effective if users tolerate biases in ethnicity and sex. Operational ease is a poor argument for disregarding fundamental rights.”

Known Issue

Internal documents show that this discriminatory flaw has been known about for over twelve months. Furthermore, law enforcement lobbied to reverse an earlier ruling that was designed to mitigate the problem.

Senior officers were notified of the algorithmic discrimination in September 2024. The government-ordered laboratory study concluded the system was more likely to suggest incorrect matches for photos of women, Black people, and those under 40 years old.

A Policy U-Turn

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

However, this directive was overturned the following month following complaints from police that the adjusted system was generating fewer “useful lines of inquiry”. Internal records indicate the stricter setting reduced the number of searches that yielded potential matches from over half to a just 14%.

Profound Inequalities

Although the authorities declined to specify what threshold is currently used, the latest independent review discovered the system could produce incorrect matches for women of Black heritage nearly a hundred times more often than for white women at specific configurations.

The Home Office commented on these findings: “Our evaluation found that in a specific scenarios the algorithm is more likely to wrongly flag some demographic groups in its match reports.”

Operational Effectiveness vs. Bias

Describing the effect of the brief increase to the system's confidence threshold, the NPCC documents note: “This adjustment greatly lessens the impact of bias across legally safeguarded attributes of ethnicity, age and sex but had a significant negative impact on operational effectiveness”. The documents further note that forces argued that “a once effective tactic returned outcomes of questionable value”.

Broader Rollout Plans

Meanwhile, the government has opened a ten-week public review on its plans to widen the use of biometric scanning systems. The minister for police the relevant minister has described the tool as the “biggest breakthrough since DNA matching”.

Criticism from Advisors and Monitors

Abimbola Johnson, head of the independent scrutiny and oversight board for the police race action plan, said: “We observed scant discussion in race action plan meetings of the facial recognition rollout despite obvious cross-over with the plan’s concerns.

“This disclosure demonstrate yet again that the anti-racism commitments policing has made via the race action plan are not being translated into broader operations. Independent assessments have cautioned that innovative tools are being rolled out in a landscape where ethnic inequalities, inadequate oversight and poor data collection already persist.

“Any use of facial recognition must adhere to strict national standards, be subject to external review, and demonstrate it diminishes rather than exacerbates racial disparity.”

Official Statement

A government representative stated: “We takes the findings of the report seriously and we have implemented changes. A updated software has been externally evaluated and procured, which has no statistically significant bias. It will be tested early next year and will be undergo evaluation.

“The foremost aim is ensuring public safety. This revolutionary tool will support police to apprehend and prosecute offenders. There is officer review in every step of the process and no arrest or charge would be taken without trained officers meticulously examining the results.”