Police forces need to do more to recruit women and people from ethnic minorities, the Home Secretary warned today - saying the current situation is "simply not good enough".
Official figures show women make up just 28 per cent of the police force, despite 51 per cent of the population being female.
And there are no forces in the country which have a representative number of black and ethnic minority officers - with four forces having no black police officers on staff at all.
Fourteen have no black women on staff, while North Yorkshire Police employs no women from any ethnic minority.
In a speech to the National Black Police Association, Theresa May set out figures showing that police forces nationwide are still largely dominated by white men.
Dyfed-Powys Police had the lowest total number of ethnic minority officers, with just eight out of 1,175 full time staff - or 0.7 per cent.
In proportion to the workforce, however, Cheshire Police came bottom, with just 0.6 per cent of officer from an ethnic minority background - or 12 out of 1,962.
The two forces, along with Durham and North Yorkshire, were found to have no black officers.
More than half of England and Wales' 43 forces also reported a decline in numbers of ethnic minority officers in 2014, the figures show.
"This is simply not good enough," Ms May said.
"I hope these figures will provide chief constables with the information they need to identify areas for improvement and for the public and Police and Crime Commissioners to hold them to account."
However, she added, positive discrimination policies were "deeply flawed" and was not the solution.
The 10 forces with the lowest actual number of ethnic minority officers are:
Dyfed-Powys - 8
Cheshire - 12
Cumbria - 13
North Wales - 13
North Yorkshire - 15
Dorset - 17
Humberside - 17
Lincolnshire - 18
Durham - 20
Gwent - 21
The Metropolitan Police reported the largest proportion of ethnic minority officers, with 11.7 per cent, followed by West Midlands Police at 8.6 per cent and Leicestershire Police at 7.2 per cent.
Ms May also used her speech to publicly refute suggestions by Met Police commissioner Sir Bernard Hogan-Howe that reforms in the way stop and search powers are used have contributed to an increase in knife crime.
It is "simply not true that knife crime is rising because the police are no longer stopping and searching those carrying knives," the conference heard.