Four out of ten crimes are written off as unsolvable just a few hours after they are reported.
The two million offences are simply "screened out" - and their victims have little or no chance of seeing the culprit brought to justice.
No officer visits the scene of the crime, and no attempt is made to find a suspect.
As many as two-thirds of burglaries are not investigated in some areas, according to the police figures.
Even robberies and violent crimes can be screened out - along with fraud, theft and vandalism.
Among the 12 English and Scottish forces which released figures under Freedom of Information laws, 788,000 crimes were screened out last year.
From a total of 2,029,000 recorded offences, this means 39 per cent are written off in this way.
The findings suggest that out of 6million offences reported to forces in the UK last year, around 2.3million were not investigated.
Shadow home secretary David Davis said: "So-called screening can have the effect of making some crimes in effect risk-free."
Police justify the screening policy by claiming it allows them to target their resources - which they say are stretched to the limit by red tape - on investigating more serious crimes.
Sunday, November 11, 2007
UK Policing... 60% of the time they try.
Police brand four out of ten crimes 'unsolvable' just hours after they are reported