Mass screening of the public at shopping centres or events like pop concerts, by police officers using facial recognition software, must be halted because it could amplify racial discrimination and stifle free expression, the equality watchdog has said.

The Equalities and Human Rights Commission (EHRC) said the technology should be suspended until its impact has been independently scrutinised and laws governing its application improved.

Police in London and south Wales have been at the forefront of using automated facial recognition (AFR) technology, which uses cameras to capture images of faces and double-checks these against databases of wanted suspects.

Scotland Yard has this year deployed cameras to scan shoppers in Stratford, east London, and at Oxford Circus in London, while South Wales police used the technology at a Slipknot concert at the Cardiff City football club stadium in January, as well as to monitor football fans.

The Oxford Circus deployment on 27 February scanned 8,600 faces to see if any matched a watchlist of more than 7,000 individuals. During the session, police wrongly stopped five people and correctly stopped one.

Prof Peter Fussey, an expert on surveillance from Essex University who conducted the only independent review of the Metropolitan police’s public trials on behalf of the force, has found it was verifiably accurate in just 19% of cases.

But last September, the high court refused a judicial review of South Wales police’s use of the technology. Judges ruled that although it amounted to interference with privacy rights, there was a lawful basis for it and the legal framework used by the police was proportionate.

“The law is clearly on the back foot with invasive AFR and predictive policing technologies,” said Rebecca Hilsenrath, chief executive at the EHRC, a statutory non-departmental public body covering England and Wales, established under the Equality Act.

“It is essential that their use is suspended until robust, independent impact assessments and consultations can be carried out, so that we know exactly how this technology is being used and are reassured that our rights are being respected.”

Artists Georgina Rowlands (left) and Anna Hart (right), of the Dazzle Club, which holds monthly walks in London to raise awareness of AFR technology and ‘rampant surveillance’. Their facepaint is to confuse the cameras. Photograph: Kelvin Chan/AP Photo

In a report to the United Nations on civil and political rights in the UK, the EHRC said: “Evidence indicates many AFR algorithms disproportionately misidentify black people and women and therefore operate in a potentially discriminatory manner … Such technologies may replicate and magnify patterns of discrimination in policing and have a chilling effect on freedom of association and expression.”

Police forces in Hull, Leicestershire, Sheffield, Manchester, Birmingham, Bradford and Brighton have also experimented with the technology in recent years, according to research by the campaign group Big Brother Watch.

The demands for the technology to be halted add to pressure from civil liberties organisations, including Amnesty International, which has described the Met’s rollout as “putting many human rights at risk, including the rights to privacy, non-discrimination, freedom of expression, association and peaceful assembly”.

Scotland Yard’s legal mandate for using live facial recognition states that the Human Rights Act recognises action in the interests of national security, public safety and the prevention of disorder or crime as legitimate aims.

Its use “in the context of fighting crime including knife and gun crime, child sexual abuse and exploitation (including online) and terrorism offences will help the MPS to achieve its law enforcement purposes”, it says.

In January 2019, the Information Commissioner’s Office commissioned research into public perceptions about its use. Of those surveyed, 58% thought it was acceptable to be stopped erroneously by the police, while 30% thought it was unacceptable.

The Metropolitan police and South Wales police have been contacted for comment.