As forensic techniques continue to improve, reports on the success of the police in using DNA analysis for solving past and present criminal cases are becoming an everyday occurrence in the media. There are two avenues by which police can collect and obtain access to DNA samples. The first is on the basis of legislation that allows the police to forcibly collec t samples in some situations. The second is through an access order granted by the court, which allows access (...) to samples from existing collections held by other parties. The purpose of this paper is to compare these two legal mechanisms that allow the police to acquire and access DNA samples. My concern is the increase in collection of DNA samples for genetic research, the moves to standardise data collection and the computerisation of medical records, may make research collections more attractive to the police. Are we are prepared for research collections to become an extension of the National DNA Database used for crime detection? In the USA a decision has been made that the police should not be allowed access to samples and information derived from ‘sensitive’ research. This article considers ‘the certificates of confidentiality’ that have been instigated by the National Institute of Health in the USA in order to prohibit such uses of research collections by the police. In this article I consider whether certificates of confidentiality should be used in the UK, as a way of providing greater protection to researchers and participants in research. (shrink)