In his annual report, released today, Police Complaints Commissioner for Scotland John McNeill says the number of applications from members of the public seeking a review of how police handled their complaint rose by 27%.
Of the 405 individual complaints detailed in reports known as complaint handling reviews, 42% were found to have not been handled to a reasonable standard by police.
In his report, the commissioner includes a complaint about Northern Constabulary to illustrate how a single issue can indicate a larger problem that may impact on police practices. This year's review uncovered a discrepancy between practice within Northern Constabulary where the use of handcuffs was "standard procedure" for anyone taken into custody and the Scottish Police Service Students Training Manual, which stated that no police force adopts such a policy.
As a result Northern Constabulary amended its internal guidance on the use of handcuffs.
Professor McNeill said: "My reviews provide a unique perspective on how different geographical areas handle similar complaints.
"From that I can draw out insights that can bring about a change within one area or wider issues that can be shared with all policing bodies in Scotland."