Every record in the NDNAD is derived from a sample of human material, usually saliva or hair. Where possible, samples are collected from crime scenes. Specialised laboratories process the samples and extract the DNA profile.
In Scotland, samples are only taken in connection with serious crimes. Anywhere else in the UK police can take a sample without consent from anyone arrested for a recordable offence*.
DNA profiles and samples are police property and are primarily used to help solve crimes and prevent miscarriages of justice. Special permission is required to use them for any other purpose such as genetic research.
Storing Samples
At the moment, the rules governing what happens to the collected DNA samples depends on where in the UK you live. Scotland and Northern Ireland have their own national databases, but also export profiles to the main NDNAD.
In Scotland, both profile and sample are destroyed if the person is not charged or convicted, and can be requested back from the NDNAD. Volunteers can also withdraw permission for their samples to be retained. DNA from innocent people is only kept under exceptional circumstances and for no more than 5 years. In the rest of the UK, both profiles and samples are kept indefinitely even if a person is innocent, and volunteers cannot withdraw their permission.
All this will change if the 2011 Protection of Freedoms Bill, currently being debated in Parliament, passes into law.
*Almost all criminal offences are recordable, including minor offences such as begging or being drunk and disorderly. Most recordable offences can lead to a prison sentence.
The case of S and Marper versus the United Kingdom
In 2008, two people who had been suspected, but not convicted of a crime, appealed to the European Court of Human Rights to have their DNA samples destroyed and their records removed from the NDNAD.
The court unanimously decided in their favour. This landmark decision had major implications on how records are stored in the NDNAD and the government was forced to act. The 2011 Protection of Freedom Bill, if adopted, will bring the law in England, Wales and Northern Ireland into line with Scotland.
