Relative Doubt: Familial Searches of DNA Databases

Michigan Law Review, Vol. 109, p. 291, 2010

58 Pages Posted: 11 Nov 2009 Last revised: 28 Feb 2014

See all articles by Erin Murphy

Erin Murphy

New York University School of Law

Date Written: November 2, 2009


The continued growth of forensic DNA databases has brought about greater interest in a search method known as “familial” or “kinship” matching. Whereas a typical database search seeks the source of a crime-scene stain by making an exact match between a known person and the DNA sample, familial searching instead looks for partial matches in order to find potential relatives of the source. The use of a familial DNA search to identify the alleged “Grim Sleeper” killer in California brought national attention to the method, which has many proponents. In contrast, this Article argues against the practice of familial searching on a variety of grounds, including claims related to equality, accuracy, privacy, racial discrimination, and democratic accountability. It then addresses the legality of the method. Lastly, in the event that arguments to prohibit the practice prove unpersuasive, this Article sets forth recommendations for restrictions on familial searches that might ameliorate their possible iniquitous effects.

Keywords: familial search, kinship search, DNA, forensic science

Suggested Citation

Murphy, Erin Elizabeth, Relative Doubt: Familial Searches of DNA Databases (November 2, 2009). Michigan Law Review, Vol. 109, p. 291, 2010, Available at SSRN:

Erin Elizabeth Murphy (Contact Author)

New York University School of Law ( email )

40 Washington Square South
New York, NY 10012
United States
212-998-6672 (Phone)

Here is the Coronavirus
related research on SSRN

Paper statistics

Abstract Views
PlumX Metrics