Police fail to record one in five of all crimes reported to them, says report
More than 800,000 - or one in five - of all crimes reported to the police each year are not being recorded by officers, a report suggests.
The problem is greatest for victims of violent crime, with a third going unrecorded. Of sexual offences, 26% are not recorded.
An HM Inspectorate of Constabulary report looked at more than 8,000 reports of crime in England and Wales.
The watchdog said the failure to record crime properly was "indefensible".
Home Secretary Theresa May described the findings as "utterly unacceptable", but police representatives said the situation had improved since the study.
The Association of Chief Police Officers said workload pressures, target culture and inadequate supervision all contributed to under-recording.
An unrecorded crime is classed as one that is reported to the police but not recorded as an offence. It means an investigation into the alleged crime is unlikely to happen.'Serious concern'
The audit reviewed reports of crime between November 2012 and October 2013 across all 43 forces in England and Wales.
It found that:
- Among the sample, 37 rape allegations were not recorded as a crime
- For 3,842 reported crimes, offenders were given a caution or a penalty notice - but inspectors believe 500 of those should have been charged or given a heavier penalty
- 3,246 of those offences that were recorded were then deemed to be "no crimes" - but inspectors believe 20% of those decisions were wrong and a crime had been committed
- The incidents recorded as "no-crimes" included 200 reports of rape and 250 of violent crime
- More than 800 of the victims were not told of the decision to "no-crime" their report
by Danny Shaw, BBC home affairs correspondent
The under-recording of crime is more than a question of getting the statistics wrong.
If an offence isn't officially logged, it may not be investigated. And without a police inquiry there's no hope of finding the perpetrator and preventing other crimes.
Inspectors say there may well be people on the streets now, able to commit more crimes, who would have been locked up had their original offence been properly dealt with.
There are indications that some forces are improving. But there's also a warning in the report that increasing workload pressures among police - who are having to do more with considerably less - will "sharpen" the incentive not to record crimes.
Chief Inspector of Constabulary Tom Winsor told the BBC that the under-recording of sexual offences was of particular concern and more sex crimes would be reported if victims felt they could trust the police.
"The police need to institutionalise a culture of believing the victim. Every time," he said.
"Now in some cases it may turn out that a crime hasn't been committed, in which case the figures can be changed later.
"But the crime needs to go on the books straight away so that the crime is properly investigated in every case and the victim receives the services which she or he should have."
Jeff Gardner, from Victim Support, told the BBC: "The police absolutely need trust of the public because if they don't have it, there's no communication and police can't police properly."
Police are obliged to inform victims about their decisions but the report found this was not always the case.
Victims may have been under the impression that their crimes were being investigated when they were not, the report said.'Wheelie bins'
The report looked at every police force in England and Wales and drew national-level statistics from its sample. But it acknowledged there were large regional differences and some forces were very good at crime recording.
West Midlands Police and Lincolnshire Police had an almost perfect record, while Dyfed Powys Police and West Yorkshire were among the worst-performing forces.
Chief Constable Jeff Farrar, lead for crime recording at the Association of Chief Police Officers, told the BBC that forces were not following the rules in the same way.
"As soon as an incident is reported, it is recorded. There's an incident on every police force's system," he said.
"Some forces are immediately recording that as a crime without any investigation; some forces are going perhaps too far in the investigation.
"But the rules do say we need to be satisfied that a crime has been committed."
He said some cases, such as a serious sexual offences, should "absolutely be recorded" but there were some occasions were the public would expect officers to ask a few more questions before recording a crime.
Providing one example from his own Gwent force, he said: "We had in one month an increase of 300 wheelie bin thefts.
"When we looked at that in a bit more detail, because we had recorded them, it would appear if you reported that as a theft you got a new wheelie bin for free from the local authority but if it was damaged, they charged you £80."'Urgent changes'
The report said relatively little firm evidence had been found of undue pressure being put on officers to manipulate figures.
But in an online survey, some officers and staff did say performance and other pressures were distorting their crime-recording decisions.
The HM Inspectorate of Constabulary (HMIC) report recommended that standard training established by the College of Policing be provided by each force.
Mrs May said there had been "utterly unacceptable failings" in the way police forces have recorded crime but procedures were improving.
"It is never acceptable for the police to mis-record crime. Failing to do so not only lets down victims, but the wider public who expect to be able to trust the integrity of police recorded crime," she said.
Shadow policing minister Jack Dromey said it was time for Mrs May to "get a grip on this and make urgent changes to the way the police record crime".
Ch Supt Irene Curtis, president of the Police Superintendents' Association, said recorded crime was a measure of demand on police resources rather than police performance.
"HMIC's report covers a period of at least 12 months ago and recognises that considerable improvements have already been made since that period," she said.
Earlier this year an interim report by Mr Winsor, covering 13 forces, made a similar conclusion that a fifth of crimes could be going unrecorded by police.
Last month, official figures showed the number of rapes reported to and recorded by police in England and Wales was at its highest ever level.
The Office for National Statistics said there were 22,116 recorded rapes in the year to June, a rise of 29% on the year before.
Separate statistics from the Crime Survey for England and Wales showed overall crime fell by 16% to 7.1 million cases.