London: Some British police officers are "barely literate" because the educational standards required to join the service are so low, it was claimed last night.

Tom Winsor, the lawyer reviewing police conditions, said reading, writing and mathematical skills had fallen "significantly" since the 1930s.

And in an extraordinary aside, he said two senior officers told him that standards were lowered to help black and ethnic minority recruits.

The claim was "astonishing" and an "insult" to anyone from such a background who wanted a career in policing, Winsor added. He suggested the public could be at risk if poor academic skills damaged the effectiveness of potentially vital evidence.

Winsor said criminal barristers sometimes "speak in contemptuous terms" of the "barely literate" quality of police evidence, and checking and rewriting paperwork was increasing the cost and bureaucracy of policing.

Speaking to an audience of superintendents in Warwickshire, Winsor said: "Why is the entrance test for a police constable now so low? The educational requirements, why are they so low? We looked at the basic questions, one of which is, you find a purse in the street, it contains a £5 note, four 20p pieces and five 2p pieces, how much is in the purse? That's the standard.

"We've looked at the educational standards for the police from 1930 and 1946 and I can tell you they are very, very significantly harder." Winsor said he was told by a former Met Commissioner and serving national Police Federation officer that standards were lowered to get more diverse applicants.

He said: "I find that astonishing because if I was of that background, I'd be insulted. Is it true, this assumption? It can't be so."

— Daily Mail