There have always been corrupt police officers –
and there always will be.
But keeping the numbers to a minimum is something that the 43 police forces in England and Wales have never done well.
Since the second world war, the police have poured resources into what was once called Complaints and Discipline and is now called Professional Standards Departments.
The major battles have taken place inside Britain’s biggest force – the Metropolitan Police. But other police forces haven’t been immune to the problem.
There have been increasingly sophisticated attempts to combat corruption but the problem remains.
REBECCA charts the often murky history of anti-corruption units in London.