The Commission for Racial Equality (CRE) has called for a governmental review of police recruitment procedures.

CRE chair Trevor Phillips said: “The revelations contained in Mark Daly’s documentary are truly shocking. This is not just a matter of a few recruits who can be trained out of their behaviour. This shows a pattern of behaviour that is widespread and, though officially condemned, is tacitly condoned by their peers.

"I will be writing to every chief constable in England and Wales asking what measures they have in place to ensure that no racist is allowed to wear a police uniform.

“I will also be asking what procedures they have in place for detecting racist behaviour.”

A Home Office spokeswoman said it would urge forces across the UK to toughen up procedures.

“Last year we introduced a new training system which we are encouraging forces to take up. There is a diversity element to this training which is much more rigorous, and if a recruit fails it they are not offered a job,” she said.