British Law Enforcement Agencies Campaign to Employ Discriminatory Facial Recognition Systems

Law enforcement agencies across the United Kingdom effectively campaigned to use a facial recognition system known to be biased against women, youths, and individuals from minority ethnic backgrounds, following complaints that a more accurate version generated a reduced number of investigative leads.

The Technology in Practice

British police utilize the police national database (PND) to conduct retrospective facial recognition searches. This procedure entails comparing a reference photograph of a person of interest against a repository of more than 19 million mugshots to identify potential matches.

Admitted Bias

The Home Office conceded last week that the technology was biased. This admission followed a study by the government's National Physical Laboratory found it misidentified Black and Asian people and women at significantly higher rates than Caucasian males. The ministry said it “took steps on the findings”.

“It prompts the issue of whether facial recognition only becomes effective if users tolerate discrimination in ethnicity and sex. Operational ease is a weak argument for overriding fundamental rights.”

Long-Standing Problem

Official papers reveal that this discriminatory flaw has been known about for over twelve months. Furthermore, law enforcement argued to overturn an earlier ruling that was designed to mitigate the problem.

Senior officers were informed of the algorithmic discrimination in September 2024. The Home Office-commissioned laboratory study concluded the system was more likely to suggest incorrect matches for images depicting women, individuals of Black ethnicity, and those aged 40 and under.

A Policy U-Turn

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

However, this directive was reversed the following month following complaints from police that the modified technology was producing a lower number of “investigative leads”. Internal records show the higher threshold reduced the number of queries resulting in possible identifications from 56% to a mere under 15%.

Severe Disparities

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

The ministry stated on these findings: “The testing found that in a specific scenarios the algorithm is has a greater tendency to incorrectly include some population segments in its search results.”

Balancing Utility and Fairness

Describing the impact of the brief increase to the system's confidence threshold, the police records note: “This adjustment significantly reduces the effect of discrimination across legally safeguarded attributes of ethnicity, age and gender but had a significant negative impact on operational effectiveness”. The papers add that forces complained that “a previously useful tool now delivered results of limited benefit”.

Wider Implementation Proposals

Meanwhile, the UK administration has launched a ten-week consultation on its plans to expand the use of biometric scanning systems. The minister for police Sarah Jones has labeled the technology as the “most significant advance since genetic fingerprinting”.

Criticism from Advisors and Monitors

The chair of a police oversight board, head of the advisory panel for the police race action plan, said: “There was very little consideration in equality strategy sessions of the technology deployment even with obvious cross-over with the plan’s concerns.

“This disclosure demonstrate yet again that the pledges to combat discrimination the police has made through the equality initiative are failing to be integrated into wider practice. Independent assessments have warned that innovative tools are being rolled out in a landscape where ethnic inequalities, inadequate oversight and faulty information gathering already persist.

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

Home Office Response

A government representative stated: “The Home Office treat the findings of the report seriously and we have already taken action. A updated software has been independently tested and acquired, which has no statistically significant bias. It will be tested in the coming months and will be subject to evaluation.

“Our priority is ensuring public safety. This revolutionary tool will support officers to apprehend and prosecute offenders. There is officer review in each stage of the procedure and no further action would be taken without trained officers carefully reviewing the results.”