Can police take my DNA?

The power to take DNA samples from suspects is set out in Part V of the Police and Criminal Evidence Act 1984. The rules were significantly reformed by the Protection of Freedoms Act 2012, which introduced tighter restrictions on how long DNA profiles can be retained.

Under PACE s.63, a non-intimate sample (such as a mouth swab for DNA) can be taken without consent from a person who is in police detention as a result of being arrested for a recordable offence. A "recordable offence" is one for which a person may be sentenced to imprisonment, plus certain other specified offences: it covers the vast majority of criminal offences.

The DNA sample is analysed to create a DNA profile, which is a digital representation stored on the National DNA Database (NDNAD). The physical sample (the swab) must be destroyed as soon as the profile has been derived.

The retention rules depend on the outcome of the case. Under the Protection of Freedoms Act 2012 (amending PACE):

If you are convicted, your DNA profile is retained indefinitely for qualifying offences (serious offences including violence, sexual offences, and burglary) and for a period following conviction for minor offences.

If you are charged but not convicted (acquitted or case dropped), your profile must be deleted unless you were charged with a qualifying offence, in which case it can be retained for three years (with a possible two-year extension approved by a court).

If you are arrested but not charged, your profile must be deleted, subject to a limited exception for qualifying offences where a chief officer can apply to the Biometrics Commissioner for retention.

You have the right to request confirmation of whether your DNA is held on the NDNAD and to request its deletion if retention is unlawful. The Biometrics Commissioner oversees the retention framework.

For volunteers who provide DNA samples to assist an investigation (e.g., mass screenings), consent must be given in writing and can be withdrawn at any time, after which the sample and profile must be destroyed.