An article I wrote during my time at the CLB was recently published – Applying the Fourth Amendment When DNA Collected for One Purpose is Tested for Another. In this article, I researched the questions: What privacy interests remain in DNA samples after they have been collected, tested, and stored by the government? Specifically, if that DNA sample is tested again for new genetic information, is that test a search under the Fourth Amendment?
Revealing genetic information can have criminal, financial, and psychological consequences for an individual. But this information can also serve important government interests. Can DNA taken from newborns be tested for criminal identification purposes? Could DNA taken from crime victims be tested to establish paternity? Can stored DNA samples be tested for genetic medical research?
If the initial collection and testing of the DNA extinguishes a person’s reasonable expectation of privacy in the entire DNA specimen, then there would be no Fourth Amendment rights implicated by further testing (although there would be some statutory protections). Determining whether a new genetic test on a retained DNA specimen is a search is complicated by the fact that DNA stores a large amount of information in a small space, and all of that information is contained in the DNA sample that has been collected and stored.
I argue that computer-search law provides a helpful framework for determining how courts would apply the Fourth Amendment to these retained DNA samples. Professor Orin Kerr’s 2005 Harvard Law Review Article, Searches and Seizures in a Digital World, lays out the different ways in which courts have determined what expectation of privacy remains after some digital information on a computer has been searched: either the physical device has been searched and no expectation of privacy remains in any files on that device (“physical device” approach) or just the files that were opened have been searched (“virtual file” approach). Professor Kerr argued that the virtual file approach is better than the physical device approach, and furthermore, that if only a portion of a file has been viewed, only that exposed data should be considered to have been searched (“exposed data” approach).
In my article, I focus on the implications for DNA testing of the approaches used by courts thus far: the physical device and virtual file approaches. Professor Kerr’s exposed data approach to digital searches, however, deserves further discussion because it captures the principle that exposure is the key aspect of determining what has been searched, which I argue becomes especially relevant in DNA searches. In digital searches, as Professor Kerr’s article explained, the relevant cases so far have dealt mostly with searches that reveal pornographic images. In such cases, there is no difference between the virtual file and exposed data approaches because the file is viewed in its entirety. Similarly, when applied to DNA searches, the outcome of the virtual file approach is indistinguishable from the exposed data approach; the best corollary to opened and unopened files is genotyped and not-genotyped nucleotides, which maps exactly to exposed and unexposed genetic information. Evaluating DNA searches in the context of these digital-search cases does not tease apart the virtual file and exposed data approaches, but it does demonstrate the utility of focusing on the role of exposure when generalizing the holdings of the virtual file cases to other types of information-rich material.
Generalizing from trends in computer law, the zone of an initial DNA-testing search would either be the entire DNA specimen (extending the physical device cases) or just the genetic information exposed during the initial test (extending the virtual file cases and in line with the exposed data approach). I argue the latter approach, which would require either a warrant or an exception to the warrant requirement before additional genetic testing can be conducted on a stored DNA specimen, strikes the better balance between allowing the government to analyze stored DNA for new purposes when necessary and protecting genetic information from being unreasonably revealed. The alternative – basing the zone of a search on the physical boundaries in a DNA specimen (where any collected cell’s nucleus contains a person’s entire genome) – would leave a large amount of genetic information unprotected.
In addition to identifying a normative and doctrinally-supported approach to protecting stored DNA specimens from unreasonable testing, I hope exploring this issue in the context of DNA searches will add to the discussion about how best to define the zone of a search of information-rich material and how the Fourth Amendment should apply in technologically-advanced searches.