[holding answer 28 November 2006]: Data on arrest and criminal histories are not held on the National DNA Database (NDNAD). However, some data are available from the Police National Computer (PNC), but not for all of the individuals with a profile on the NDNAD. Data provided by the Police Information Technology Organisation (PITO) from the PNC indicate that at the end of November 2006 there were 86,385 persons with a DNA profile on the NDNAD taken by Essex Police who also had a record retained on the PNC. The PNC records relating to approximately 2,500 other individuals with a profile on the NDNAD had been removed from the PNC, for example, because they had not been convicted of an offence or because proceedings were discontinued.
Of the 86,385 individuals with a record on PNC, 34,647 have no conviction recorded on the PNC. However, of these, a further 22,006 have another sanction detection recorded on the PNC: for example, a caution, reprimand or final warning. The number of individuals with no conviction, caution, reprimand or final warning is 12,641. The figure of 12,641 will comprise: persons who have been arrested for a recordable offence but no further action is taken; and persons who have been charged with a recordable offence and the proceedings are on-going.
No corresponding information is available for the Mid-Essex Division within Essex Police.
[holding answer 28 November 2006]: As at 1 November 2006, there were an estimated 89,156 individuals with a DNA profile on the National DNA Database (NDNAD) taken by Essex police. These individuals would have been arrested, detained in a police station and had a DNA sample taken by Essex police, but would not all necessarily be resident in Essex.
Information on the number of individuals with a DNA profile on the NDNAD is held on a police force area basis. It is also held by police station code, but not by police force division. It is not possible to provide data for an individual division within Essex police force area without an analysis of the police stations within each division and of any boundary changes to the Essex divisional structure that have taken place since 1995 (when the NDNAD was established).
It is not possible to provide the information requested for the Wantage parliamentary constituency as the DNA subject sample records held on the National DNA Database (NDNAD) relate to police force area, not to parliamentary constituency area or local authority area. However, data are available for Thames Valley police which covers Berkshire, Buckinghamshire and Oxfordshire including Wantage.
It is estimated that as at early December 2006 there were approximately 103,600 individuals with a DNA profile on the NDNAD taken by Thames Valley police (TVP). These individuals would have been arrested, detained in a police station and had a DNA sample taken by TVP, but would not necessarily be resident in the TVP force area.
At 10 December 2006, there were an estimated 3,706,399 individuals with a DNA profile on the National DNA Database taken by the police. It has been the policy of successive Governments neither to confirm nor deny in response to questions about the activities of the intelligence and security agencies.
It is not necessarily straightforward to say that an arrest is made on the basis of DNA evidence, as police investigations will often involve looking at several different types of evidence including DNA, and an arrest may be made on the basis of the whole package of evidence. We are, however, aware of two cases in which arrests were made on the basis of mistaken DNA evidence since the establishment of the NDNAD in 1995.
In October 1997 a bloodstain from the burglary of a dwelling was matched to a Mr. K who was arrested by the Metropolitan Police. In fact samples provided by Mr K. and Mr. H had been accidentally switched in the laboratory. Mr K. began legal action against the Forensic Science Service but did not complete it within the legally prescribed period.
In August 1999, Mr. E was arrested on the basis of a DNA sample found in a burglary 150 miles from his home. He was suffering from Parkinson's disease and could not have got to the crime scene unaided. This was an SGM match—use of the more discriminating SGM plus technique (explained as follows) showed the first match was incorrect and the charges were dropped.
These errors must be seen in the context of almost 300,000 matches between crime scenes and individuals during the period 1998-99 to 2005-06. Use of DNA profiling is an extremely reliable technique.
Continuous quality monitoring of suppliers is carried out through the NDNAD's supplier accreditation section, and barcode and electronic document scanning systems are used in laboratories to minimise the possibility of human error.
The SGM technique introduced in 1995 looks at six areas of DNA plus the area showing the person's sex and has a one in 50 million chance of being incorrect (the odds are very probably much better than this).
Home Office Circular 58/2004 and the ACPO DMA Good Practice Guide advise that where a match of a crime scene to an individual involves an SGM profile, strong consideration should be given to upgrading the SGM profile to SGM Plus to ensure that there is still a match.
If a person is to be charged on the basis of a DNA match, the CPS require that there must be supporting non-DNA evidence available to be used in evidence. No-one is ever prosecuted solely on the basis of a DNA match; the DNA evidence is one piece of the information that the courts would require for a successful prosecution.