Almost one in 10 police officers in England and Wales is on sick leave or performing limited duties, according to new figures published today.
Almost 9,500 are on restricted duties due to ill-health, The Times reports.
A further 2,000 are on long-term sick leave and have been off work for at least one month.
The figures emerged in data obtained by The Times after it submitted Freedom of Information requests on each of the 43 police forces in England and Wales.
A Home Office spokesman said the responsibility for decisions about whether an officer retires on ill-health grounds or placed on restricted duties was a matter for the Chief Constable of the force concerned.
The spokesman said: "Restricted duties allows officers who are unable to undertake the full range of police duties to remain a police officer with restricted responsibilities rather than to be retired on grounds of ill-health.
"Recuperative duties are a temporary arrangement while officers recover from sick leave."
There are 1,902 officers on long-term sick leave in England and Wales, according to the figures.
These officers receive their full salary for the first six months and then half pay for the next six months, the newspaper found.
The Police Federation said that many of the 6,086 officers with long-term health problems on "restricted duties" should be allowed to retire.
Police Federation chairman Paul McKeever said: "The artificial cap on people being allowed to retire due to ill-health - no more than six officers per thousand a year - was seemingly plucked out of thin air by the Home Office.
"To make an arbitrary decision and put an artificial cap on is ridiculous and ludicrous.
"It means that many officers who have no likelihood of returning to frontline duties are able to retire.
"Officers who have served their communities and, through no fault of their own, have become unable to perform their duties are being accused of swinging the lead and malingering."
Chief Constable Peter Fahy, Association of Chief Police Officers (Acpo) lead for workforce development, said: "Police chiefs want to be fair by those officers who have been injured on duty or who have suffered from stress-related problems due to the sort of incidents they deal with.
"However, during hard economic times, the number of officers on restricted duties is a real concern and we have asked the Home Office review to deal with this matter.
"Previously there was concern about the number of officers getting medical pensions and, as a result, officers have been kept in office positions. This cannot be a long-term solution."
The figures show that nearly one in seven police officers in Warwickshire is on sick leave or on restricted duties.
In Cambridgeshire there was one in 24. West Yorkshire Police has 465 officers on restricted duties.
The Metropolitan Police Service, the country's biggest police force, has 2,163 officers on restricted or recuperative duties and 300 on long-term sick leave.
A Scotland Yard spokesman said occupational health advisers were used to minimise the number of officers placed on limited duties or long-term sick leave.
"Despite the physically and mentally demanding nature of police work, absenteeism rates in the Met are low, ahead of most public sector organisations and other police services."
West Midlands Police, the country's second largest police force, has 149 officers who have not worked for longer than a month and 560 on limited duties.
A spokeswoman for West Midlands Police said: "Given that we have around 9,000 officers, the number on long-term sick leave is relatively small."