Am I my brother's keeper? Familial DNA searches in the twenty-first century.

• Author: McCarthy, Mary

INTRODUCTION

Over twenty-five years ago, British researcher Alec Jeffreys discovered DNA fingerprinting, (1) a technique used to identify the unique genetic material of an individual by analyzing sequences of deoxyribonucleic acid (DNA). (2) Today, DNA fingerprinting has expanded from a fledgling tool of law enforcement to a ubiquitous, valuable asset in criminal investigations and prosecutions. Correspondingly, criminal DNA databases have grown in size and function, ushering in a new advent of DNA searches. For example, "familial DNA searches" compare crime scene DNA evidence to offender profiles already in a DNA database, searching for a partial DNA match in the hopes that the perpetrator is a relative of an offender whose profile is already present in the database. (3) In July of 2010, California's use of familial DNA searches came to the forefront of the public eye with the arrest of Lonnie D. Franklin Jr., the alleged "Grim Sleeper" serial killer who may have been responsible for at least ten murders in the South Los Angeles area over a period of twenty-five years. (4)

Often called "familial" DNA searches, partial match DNA searches have been used in criminal investigations and in missing person identifications. Although the United Kingdom pioneered the use of familial DNA searches in criminal investigations, recent efforts in California and Colorado indicate a growing interest in the use of familial DNA searches in America. (5) However, familial DNA searches implicate concerns over false positive results and placing family members of offenders, whose DNA profiles remain in a DNA database, under lifelong genetic surveillance. Also, because minorities constitute a disproportionate percentage of offenders in DNA database systems, familial searches may have a disproportionate effect on minority communities. Such concerns are of even greater importance because recent state and federal laws are beginning to allow DNA collection from arrestees, rapidly expanding the pool of available DNA profiles. With these changes occurring, society and national and state governments must address the growing role of DNA profiling in the American criminal justice system.

Part I addresses the recent interest in familial DNA searches, while Part II analyzes the combined effects of allowing familial DNA searches in criminal investigations when DNA databases are expanded by requiring DNA samples from arrestees, in particular looking to California as a prototype. Part III asks whether these changes in the size and function of criminal DNA databases are a "database creep" (6) or the inevitable result of DNA profiling. This Note concludes that there are weak legal objections to expansions in the size and function of DNA databases while there are strong policy objections. Also, California is a likely prototype for other states interested in performing familial DNA searches and collecting DNA samples from arrestees. In addition, a universal DNA database is beginning to be recognized as a serious possibility and potential solution to disparities in nonuniversal, expanded DNA databases. This Note concludes that there should be greater discussion of the advantages and disadvantages to DNA profiling and expansion in the size and function of DNA databases.

1. THE EMERGENCE OF FAMILIAL DNA SEARCHES

   1. The Use of DNA Profiling

      DNA profiling has been a useful tool for law enforcement, and law enforcement agencies are eager to see expansion in DNA database use and size. (7) DNA profiling can augment criminal investigations in many ways. A majority of crimes are committed by repeat offenders, (8) an important reason why DNA profiling is an effective tool. (9) DNA databases would likely provide more hits if criminals' "DNA profiles [could] be entered into the system early in their career, [so that] they can be identified when future crimes are committed." (10)

      Because DNA matching "may succeed when other forms of forensic or witness evidence has proved insufficient or unreliable in helping bring offenders to justice for crimes committed some years earlier," (11) it is increasingly used to generate suspect leads rather than support incriminating evidence against a previously identified suspect. However, DNA profiling remains useful as support for other incriminating evidence against a previously identified suspect, and DNA profiling can provide an "increased likelihood of generating reliable and persuasive evidence for use in court" as well as "a reduction in the cost of many investigations." (12) And of course, DNA profiling is an important postconviction tool to secure exoneration for innocent individuals. (13)

      Other advantages of DNA profiling are "the likely deterrent effect of DNA databasing on potential criminal offenders[ ] and a possible increase in public confidence in policing and in the wider judicial process." (14) And DNA profiling has its uses outside the criminal justice system--in combination with family reference samples, it can be used in missing persons investigations, paternity testing, and mass disaster victim identifications. (15)

      DNA profiling analyzes the genetic sequence of individuals. DNA is found in each cell of the human body (16) and provides a "genetic blueprint" for each person, (17) storing information in a sequence of four possible molecules called bases: adenine (A), thymine (T), cytosine (C), and guanine (G). (18) DNA is composed of two strands of paired bases (A paired to T, and G paired to C) in varying combinations. (19) There are approximately three billion base pairs in the human genome; consequently these four possible bases yield trillions of combinations. (20)

      In human cells, DNA is packaged into forty-six different chromosomes. (21) A person receives half of his or her DNA from his or her mother and half from his or her father, so one chromosome in each chromosomal pair is derived from each parent. (22) Additionally, DNA has "coding" regions--known as genes, which provide molecular instructions for making proteins--and "non-coding" regions, otherwise known as "junk DNA" because these regions do not appear directly related to protein production. (23) A "locus" refers to a gene's (or DNA marker's) location on a chromosome. (24) Only about 0.3% of human DNA differs between individuals, (25) but DNA profiling examines multiple markers at certain loci to compare genetic variations and identify individuals. (26) A DNA profile is the combination of genetic variations obtained from multiple loci. (27) DNA profiling can be completed using small amounts of DNA found in biological material such as blood stains, saliva, bone, hair, or semen. (28) Only a small amount of DNA sample is needed because the DNA can be amplified into enough copies for testing in a laboratory. The majority of DNA profiling uses a process called Polymerase Chain Reaction (PCR), which yields many copies of a particular DNA sequence. (29)

      When there is enough DNA, it is examined for variations in repeated DNA sequences. The human genome is full of repeated DNA sequences. (30) DNA regions with repeated units two to six base pairs in length are called microsatellites or short tandem repeats (STRs) and are popular DNA repeat markers because: (1) they are easily copied through PCR, and (2) the number of repeats in STR markers can be highly variable among individuals. (31) STR loci used as markers have been standardized in order to be effective across a wide number of jurisdictions. (32) For example, the U.S. national DNA database, CODIS, uses thirteen core STR loci, (33) for a total of twenty-six markers to compare the genetic variations between individuals. (34)

      In addition, although most DNA profiling examines DNA markers on non-sex chromosomes, (35) other types of DNA testing are available. Constituting a minority of DNA testing, Y-chromosome and mitochondrial DNA markers can be used to trace paternal and maternal lineage, respectively, (36) and may be important to the future of familial searches. (37) For example, courts in Maryland and Michigan have permitted the use of mtDNA evidence in a murder conviction. (38)

      The size and function of criminal DNA databases have dramatically expanded in the past several years. (39) The three largest DNA databases in the world are maintained by, in descending order, the United States, (40) the United Kingdom, (41) and California. (42) Each of these databases has been expanded to include DNA samples from arrestees. (43)

      The United States national DNA database is known as the National DNA Index System (NDIS) and is comprised of a system of DNA profiles submitted by national, (44) state, (45) and local (46) law enforcement agencies, (47) totaling fifty-two State DNA Index Systems (SDIS) and 126 Local DNA Index Systems (LDIS). (48) The NDIS system contains offender DNA profiles, forensic (crime scene) DNA profiles, and missing person DNA profiles. (49) The DNA profiles in the NDIS are searched weekly for matches, and results are returned to the laboratory that originally submitted the matched DNA profile. (50)

      There are some restrictions on both the types of profiles submitted and the use of DNA profile information. States must agree to adhere to FBI-issued quality assurance standards in order to include profiles in the NDIS. (51) Federal requirements are imposed on states through participation in the NDIS (52) or through their receipt of federal DNA grant funding. (53) NDIS access can be cancelled if these requirements are not met. (54) To be included in the NDIS offender index, a complete DNA profile of the thirteen STR core loci is required, while at least ten of the thirteen STR core loci are required to upload a forensic profile. (55)

      The Combined DNA Index System (CODIS) is the automated DNA information processing and telecommunication system that supports NDIS. (56) CODIS was "developed specifically to enable public forensic DNA laboratories to create searchable DNA databases of...