Ethical and legal reflections on secondary research using genetic data acquired for criminal investigation purposes

Research with human genetic data or human beings more generally requires valid informed consent. However, several exceptions exist to this universal principle, usually for situations where it is impossible or at least impractical to obtain this consent. Those exceptions are usually bound to requirements of necessity, shared benefit for the concerned community and minimization of harmful impact. Research without consent is normally subject to approval by an ethics review board. However, secondary use for research may also be based on statutory research privileges in the law. We identified several legal provisions in different countries, permitting the secondary use of DNA data that has been collected without consent for law enforcement purposes, which raises ethical questions. Most of the respective laws seem to be connected to privacy rules and permit the use of de-identified data only. However, whether individual DNA profiles in suspect and offender databases can actually be de-identified must be questioned. What appears to be less critical in terms of re-identification risk are the frequently mentioned "statistical indices", most likely referring to aggregated allele frequencies. However, reflections about data anonymity and a narrow purpose limitation to research aiming at the improvement of calculations of weight of evidence seem not to be the sole reasons for permitting research with entries from criminal offender databases. Distinctions between convicted offenders and other people in the database suggest an assumption of forfeiting some level of privacy protection upon conviction underlying some of these provisions. The use of entries on national DNA databases could therefore amount to problematic additional punishment.