The number of complaints against police in England and Wales rose by 44% in the last year, statistics show.
The rise is not thought to be due to a change in the way officers behave
Figures published by the Independent Police Complaints Commission show there were 22,898 complaint cases in 2004/5.
However, the report says there is no evidence to suggest that the increase is due to a sudden change to the way in which the police behave.
Instead it cites improvements in accessibility and recording procedures as reasons for the rise.
More complaints that might never have been presented or that would have been dealt with informally are now recorded, according to the report.
BBC Home Affairs Correspondent Andy Tighe said: "A lot of rank and file officers are pretty fed up about the amount of time they say is being used on investigations they say are going nowhere."
However, he pointed out that the IPCC said this issue was being addressed and this was evident from the findings showing an increase in allegations dealt with locally and a corresponding reduction in full-blown investigations.
The statistics revealed regional variations.
The number of complaints increased by 198% in Northamptonshire, by 156% in West Mercia and by 141% in Staffordshire.
Although the majority of forces registered a rise in complaints, there were 16% fewer complaints in the City of London and 5% less in Derbyshire.
"The report contains much good news," said IPCC chairman Nick Hardwick.
He said the findings suggested that the system of handling complaints is becoming "more accessible and less bureaucratic".
"People are more confident about raising their concerns but getting these resolved more simply and quickly.
"That is good news for the public and police officers alike."