The police watchdog has removed a controversial, pseudoscientific term from response forms after criticism that it increased police brutality.

So-called ‘excited delirium’ has previously been listed a relevant factor in police intervening in an incident, but evidence shows it has been disproportionately used to label men from ethnic minorities. The, now rejected, term has particularly been used to justify restraining people in a state of acute distress, often caused by drugs or mental illness.

Although it has never been a settled medical diagnosis, ‘excited delirium’ has fed myths about people exerting super-human strength, or an inability to feel pain, which have then motivated more heavy-handed responses by police. The Royal College of Psychiatrists has said the term plays into racial stereotypes and police should not use it to describe someone’s behaviour or state of mind.

The Independent Office for Police Conduct (IOPC) have now removed the term from official referral forms. A spokesperson told The Observer the body had ‘decided to stop using the term ‘excited delirium’ as we recognise that it is language which is outdated and potentially offensive.’

‘We are in the process of removing it from IOPC forms that police forces use to make referrals to us and will not use the term as an option for categorising our investigations.’

The watchdog will continue to use the term ‘acute behavioural disturbance’, which has also been criticised by campaigners, and remains similarly controversial. The IOPC said they will continue to use this term to describe people’s behaviour to ensure consistency, as it is currently used by coroners.

The controversy surrounding law enforcement’s use of ‘excited delirium’ exploded in 2021 when it was used in the trial of Derek Chauvin, killer of George Floyd, to describe Floyd’s actions on that day.

Campaigners in Britain say that ‘acute behavioural disturbance’ is routinely cited as a factor following deaths – predominantly of black men – after contact with the police.