DNA retention after arrest: balancing privacy interests and protection

The S & Marper judgement of the European Court of Human Rights addresses the question of DNA profile retention in the absence of conviction or admission of guilt. It casts the problem as a question of balancing the principles of individual privacy and public protection. In the Court's view there is a level of public protection conferred by retention of DNA from arrestees against whom no further action is taken which would justify retention, yet relevant data do not exist to determine the level of public protection gained by such retention. A pilot study is reported here showing that a group against whom arrest is followed by no further action exhibits levels of subsequent criminality (measured by frequency, latency and most severe outcome) similar to those of people officially processed by sentence or caution. Survival and count regression analyses suggest statistical approaches to be taken using larger and better samples. A research programme is outlined which would allow evidence-based policy on DNA profile retention