Monthly Archives: June 2012

The Arizona Supreme Court Adopts a No-Peeking Rule for Juvenile Arrestee DNA

Preface: This posting (of June 29) replaces one from June 28. Part of that initial discussion of the Arizona Supreme Court’s opinion was, I think, unwarranted. In particular the criticism of the court’s treatment of the state interests may not have been accurate. Complex opinions, like good literature, rarely can be fully grasped on a first reading.

* * * A few days ago, the Supreme Court of Arizona promulgated a creative “don’t peek” rule for DNA samples routinely taken from juveniles before a finding of delinquency. Justice Andrew Hurwitz (who has just moved to the U.S. Court of Appeals for the Ninth Circuit) penned the unanimous opinion in Mario W. v. Kaipio, Commissioner, No. CV-11-0344-PR (Ariz. June 27, 2012). The opinion injects some new ideas and analysis into the legal controversy over arrestee DNA sampling, but I have to question whether the reasoning is sufficient to support the result the court reaches and to ask how far the court’s theory of Fourth Amendment privacy extends.

At the outset, the Arizona court quite properly sets out the normal rule that Fourth Amendment reasonableness requires a warrant and probable cause unless a categorical exception to these requirements exists. But then the court states that “[t]he parties do not dispute the applicability of the totality of the circumstances test, and we therefore analyze the Arizona scheme under that rubric.” This is hardly a ringing endorsement of this mode of analysis, but it is the way most courts approach the issue [1].

Getting to the specifics of DNA sampling on arrest, the court observes that there are “two separate intrusions” and “two searches — ‘the physical collection of the DNA sample’ and the ‘processing of the DNA sample.'” The former observation is basically correct. “The seizure of buccal cells is a physical intrusion, but does not reveal by itself intimate personal information about the individual.”1/

But the laboratory analysis probably is not a “later search.” The U.S. Supreme Court, at any rate, has yet to hold that physical testing or inspection is a separate search simply because it produces information about the substance being analyzed. Indeed, the Court, in two opinions–United States v. Edwards, 415 U.S. 800 (1974), and United States v. Jacobsen, 466 U.S. 109 (1984)–has held the opposite.

The Arizona court relies on an analogy to containers. It maintains that human cells are like steamer trunks or purses that contain private possessions. The police engage in a search when they open such a container and rummage through its contents.

The analogy looks good at first blush. People surely have reasonable expectations of privacy in the contents of their luggage and their purses. The Orthodox Jew on Yom Kippur with an apple core in her purse, the Catholic juvenile with birth control pills in hers, and the English literature professor with sleazy novels in his trunk all have a fair claim to freedom from unregulated intrusions into their purses or luggage. The police will all but inevitably espy these legal but embarrassing items if they look through the container without a warrant.

But compare this with the laboratory analysis of the epithelial cells. The laboratory extracts a single kind of molecule–DNA. It does not look at the rest of the cell. Within the DNA, it looks at a tiny fraction of the genome–locations (“loci”) that are not potentially embarrassing (except insofar as they match crime-scene samples).1/ The situation begins to resemble cases in which dogs that (supposedly) alert only to drugs are used to sniff luggage–and that, the Court has twice held, is not a search.2/

Because the government does not look through the parts of genome in which an individual has a strong expectation of privacy, a better analogy is required. Imagine, then, that every time a person commits a crime, a mysterious being delivers an envelope to the police that always contains only two things–a card with the name of an individual who was at the scene of the crime (but not necessarily at the time the crime occurred) and a key to a safe deposit box in that person’s name. Is opening the envelope a “search” that triggers the need for a warrant or an exception to the warrant requirement? Maybe, but the cases and the doctrine cited in Mario W. are insufficient to establish this result. All that the container cases establish is that the police must abide by the constitutional requirements for searches before and when they use the key to open the safe deposit box. The box, of course, is the vast part of the human genome that the police do not open in DNA testing for identity. In DNA profiling for law enforcement databases, they only read the name on the card.3/

Yet, whether one denominates the laboratory analysis as a separate search is not decisive. It might be a constitutionally permissible, warrantless, probable-causeless search, at least under the totality-of-the-circumstances balancing test. The Arizona justices reject this conclusion in favor of the following rule: (1) the state’s “important interest in locating an absconding juvenile and, perhaps years after charges were filed, ascertaining that the person located is the one previously charged” justifies collecting the sample–“even if a formal judicial determination of probable cause was not made at the advisory hearing.” However, (2) no combination of state interests justifies the warrantless laboratory analysis of the DNA sample (a) to determine whether it matches unsolved crime samples or (b) to have a profile in a database that will identify the juvenile as the contributor of DNA found in future crimes.

But why is taking DNA solely for “locating an absconding juvenile” so critical when the state already takes fingerprints that can be used this purpose? Doesn’t the fingerprint on file eliminate the need to house the DNA as well, as the Maryland Court of Appeals recently reasoned in King v. State, 42 A.3d 549 (Md. 2012)?

The Arizona court’s answer is that “[o]ne arrested for a serious crime may be fingerprinted before a judicial determination of probable cause. … A judicial order to provide a buccal cell sample occasions no constitutionally distinguishable intrusion.” This suggests that the state can choose either fingerprints or DNA as the source of identifying marks. However, if a DNA profile is “intimate personal information about the individual” merely because it constitutes “uniquely identifying information”–which is all that Mario W. says about informational privacy–then fingerprints are equally “intimate personal information.” They too provide “uniquely identifying information.” Indeed, they are better for this purpose, for they permit differentiation of identical twins.

So does Mario W. prohibit the state from examining the minutiae in fingerprints unless or until arrestees are convicted (the no-peeking rule)? From running an arrestee’s print against a database of prints from unsolved crimes? From adding the fingerprint to the national Automated Fingerprint Identification System database (AFIS) before that point? Of course, DNA loci might be significantly more threatening to privacy than fingerprint details, but that conclusion is far from obvious [1].

In analyzing the state’s interests in pre-conviction DNA analysis, the opinion correctly notes that the value in solving unrelated crimes (and in deterring future ones) is reduced considerably by two features of the Arizona law. As with all pre-conviction profiling and databasing, many of the arrestees would have their samples analyzed and included in the state database after they are convicted anyway. As for the ones who are not convicted, the Arizona law does not permit continued use of the profiles. Thus, the opinion notes, with current technology and staffing, the government has the benefit of the profiles for only a month or so (for those who not adjudicated delinquent) and for only an extra month or so for the others.

These points help explain the court’s balancing, but how enduring are they? Advances in technology, making it possible to analyze profiles in a matter of hours, easily could extend the period of pre-conviction use. In addition, what would happen if the law did not require the samples to be removed from the database in the event that the state does not prove delinquency? Obviously, that would advance the state’s law enforcement interests (although it might not be politically popular). The sad fact is that lots of people who are arrested but never convicted commit later crimes. If DNA is to be believed, California’s “Grim Sleeper” killer is one. Lives would have been saved had his profile been acquired at his first of sixteen arrests and kept in a state database. Of course, the mere fact that law enforcement could gain by keeping tabs on more people does not make all such practices constitutional. Still, it adds something to the state’s interests that is missing in the Arizona system of juvenile arrestee DNA databasing and that would have to be considered in totality balancing for the more extended system.

Interestingly, the Mario W. court intimates that expungement is mandatory “given the constitutional presumption of innocence” and the fact that those accused of crimes “do not forfeit Fourth Amendment protections.” This part of the opinion raises several puzzles. Given the history and cases on the presumption of innocence, it is an expansive reading of the presumption [2]. Moreover, if the presumption does mean that the state may not include DNA profiles of those arrested but not ultimately convicted in databases, what of fingerprints, which are retained indefinitely? As noted earlier, the court’s theory as to why DNA profiling invades informational privacy seems to apply with equal force to AFIS databases. That people do not forfeit Fourth Amendment rights just because they are accused of crimes–or, for that matter, convicted of them–is important, but it does not imply that the Fourth Amendment is an absolute barrier to suspicionless profiling and databasing. The opinion asserts that

[O]ne accused of a crime, although having diminished expectations of privacy in some respects, does not forfeit Fourth Amendment protections with respect to other offenses not charged absent either probable cause or reasonable suspicion. An arrest for vehicular homicide, for example, cannot alone justify a warrantless search of an arrestee’s financial records to see if he is also an embezzler.

As with the purse and the trunk, the financial records of the arrestee merit strong Fourth Amendment protection (unless, according the U.S. Supreme Court, they are held by a bank or other third party). But what is it about the DNA loci that merits similar protection? The state’s claim is not that an arrest justifies every unrelated search. It is (or should be) that the custodial arrest justifies using identifying marks–whether they are within fingerprint impressions or DNA molecules–for identification of the person and then for speculative searching against the marks left at past and future unsolved crimes.

To be sure, a sensitive balancing of individual and public interests might lead to the conclusion that the latter goes too far. But the assumption in Mario W. seems to be that tokens of an individual’s identity are inherently “intimate personal information” that impose a “serious intrusion on … privacy interests.” Without a clearer and more convincing analysis of the actual privacy interests associated with the many things that mark us as individuals–DNA profiles, fingerprints, iris scans, even photographs–Mario W. raises more questions than it answers.


1. One can quibble with the term “seizure,” for the extraction of the cells in the inner surface of the cheek does not seem to be a seizure in the Fourth Amendment sense. Unlike keeping a person away from his home or luggage or stopping him, it is not a substantial interference with the individual’s use of his possessions or his person. It is, however, probably a search under Cupp v. Murphy, 412 U.S. 291 (1973) (physical intrusion under fingernail), Schmerber v. California, 384 U.S. 757 (1966) (physical intrusion with syringe), or United States v. Jones, No. 10-1259 (U.S. Jan. 23, 2012) (the GPS tracking case that applied a trespass-with-intent-to-acquire-information test for ascertaining a “search”).

2. But Caballes and Place also are distinguishable in that DNA loci are not contraband.)

3. How much, if any, other information the card contains is an interesting question.

4. I am oversimplifying. When profiles from putative close relatives are available, the loci can be used for kinship testing. For example, if the state has the profiles of a mother-father-child trio, it could determine whether they are in the specified biological relationship or whether, for example, someone else is the biological father. The reader is invited to make his own comparison between the strength of the privacy interest in the contents of all manner of containers of personal effects and records on the one hand, and the STR loci used for identification, on the other.


1. David H. Kaye, A Fourth Amendment Theory for Arrestee DNA and Other Biometric Databases, 15 U. Pa. J. Const. L. No. 4 (forthcoming Apr. 2013).

2. David H. Kaye, Drawing Lines: Unrelated Probable Cause as a Prerequisite to Early DNA Collection, 91 N. C. L. Rev. Addendum No. 1 (forthcoming Oct. 2012)

Postscript: Rereading the Mario W. opinion yet again, the following paragraph struck me:

�26 The State argues that once it has lawfully obtained the cell samples, the Fourth Amendment provides no greater bar to the processing of those samples and the extraction of the DNA profile than it does to the analysis of fingerprints. But the State’s reliance on the fingerprinting analogy here is misplaced. Once fingerprints are obtained, no further intrusion on the privacy of the individual is required before they can be used for investigative purposes. In this sense, the fingerprint is akin to a photograph or voice exemplar. But before DNA samples can be used by law enforcement, they must be physically processed and a DNA profile extracted. See Erin Murphy, The New Forensics: Criminal Justice, False Certainty, and the Second Generation of Scientific Evidence, 95 Cal. L. Rev. 721, 726-30 (2007).”

This is a distinction without a difference. First, in both fingerprinting and DNA analysis, a sample (an exemplar) must be collected from an arrestee. Elsewhere, the opinion describes the intrusion on the individual in this step with unusual clarity. Second, with both fingerprinting and DNA profiling, the physical sample must be examined “before [the] samples can be used by law enforcement.”

The fingerprint information lies in minutiae that must be studied by eye or by computer to extract useful data. The DNA information lies in particular loci that must be characterized by chemical reactions and computers to extract useful data. What matters is not the physics or the chemistry, but the transformation into identifying information. If extracting this information is a separate search for DNA, then extracting the identifying information also is a separate search for fingerprints. If this “second search” requires a warrant for DNA, it requires it for fingerprints.

Cross-posted to Forensic Science, Statistics, and the Law

CODIS Loci Ready for Disease Prediction, Vermont Court Says

A trial court in Vermont has gone where no court has gone before. In State v. Abernathy [1], Chittenden Superior Court Judge Alison Sheppard Arms found that because “[s]ix CODIS loci … have associations with an increased risk of disease or have functional properties,” the custodians of law enforcement DNA databases can make “probabilistic predictions of disease.” According to the judge, modern research has established that “some of the CODIS loci have associations with identifiable serious medical conditions,” making the scientific evidence “sufficient to overcome the previously held belief[s]” about the innocuous nature of the CODIS loci.

Emphasizing this finding that richly information-laden STR profiles reside in identification databases, the court proceeded to strike down “Vermont’s new pre-conviction DNA testing requirement … that requires submission of a DNA sample from a ‘person for whom the court has determined at arraignment there is probable cause that the person has committed a felony … .'” In an atypical opinion, the court applied a “special needs” balancing test, placed the burden of proof on the state, and held that this law violates the state constitution.

A major theme in Judge Arms’ discussion of human genetics is that there has been a revolution in our understanding of what used to be called “junk DNA.” Even though the CODIS loci originally were described as “junk” in “good faith,” that understanding was wrong–we now know that even DNA that does not code for proteins is biologically important.1 Other judges, advocacy groups, and at least one law professor have jumped from the discovery that the triplet code for proteins is not the sole message inscribed in DNA to the conclusion that all the CODIS loci may well convey significant information about disease states or propensities.

There are a couple of problems with this reasoning. All that we actually know is that some non-protein-coding DNA regulates gene expression. Scientists do not believe that all non-protein-coding sequences are regulatory. In particular, whether noncoding, nontranscribed, and largely nonconserved sequences are part of a regulatory system (even if their presence might have some function) is far from established.2 The opinion cites an essay I wrote making this point [3] but then ignores its content. It quotes the legal treatise, Modern Scientific Evidence, for the view that “while it is generally agreed that no single loci [sic] contains a gene that definitively determines any discernible characteristic of significance, there are nonetheless indications that they may play a role in some sensitive matters, and continued debates about their importance.” Before Abernathy, it appeared that the “continued debates” ended five years ago with agreement on what already was known — that even if the loci do not play a functional role, they might, like certain fingerprint patterns or blood types, have some statistical associations with diseases.3

Venturing beyond the inconclusive generalities like these, Abernathy refers to the biomedical literature on five loci and to a testifying expert’s characterization of the literature (with no specific references) on another locus. The opinion does not give the magnitude of any putative association, let alone any measure of predictive utility.4. It uses the following phrases: “a fairly large effect size,” “a modest association,” “not the most strongly associated,” “small but … not zero,”5 and “cannot find that this marker has no association.” It does not provide measures of the uncertainty in these estimates. Finally, the opinion does not discuss the extent to which the studies said to prove that the associations have been replicated.6

Of course, few judges could confidently review the flood of studies on human genetics. Unlike some previous opinions and law review articles, however, this opinion does not rely entirely or largely on newspaper headlines and stories about “junk DNA.” Here, the iconoclastic findings came after an evidentiary hearing. But, as has happened before with DNA evidence [8], the evidentiary hearing was one-sided. The defendants presented the testimony of Professor Gregory Wray of Duke University, a specialist in genetics and evolutionary biology, and the state did not to present an expert in medical genetics or genomics to counter his testimony. Although Professor Wray reviewed the biomedical literature before he testified, the defense submitted no written report, and the state rather than the defense introduced the papers cited in the opinion as exhibits. Scanning the testimony, it seems to me that Dr. Wray never was asked a series of critical questions:

  1. Is it generally accepted that the associations he pointed to apply to the population of individuals whose DNA is placed in law enforcement databanks?
  2. Assuming that they do apply to that population, what is the positive and negative predictive value of any inference about disease status or propensity derived from these particular CODIS alleles?
  3. How would the predictive or diagnostic disease-related information in a state DNA database compare to that of (a) color photographs, (b) fingerprints, (c) blood types used in conventional serology, and (d) the HLA-A and HLA-B haplotypes that used to be a mainstay of parentage testing?
  4. Are the CODIS genotypes likely to be substantially more predictive in the future?

Until these questions are answered, there is reason to ask whether the trial court’s findings fairly represent the status quo or instead are grim predictions of what could come to pass.


1. For a short audio clip reporting on the revolutionary discoveries, click on Joe Palca, Don’t Throw It Out: ‘Junk DNA’ Essential In Evolution, All Things Considered, Aug. 19, 2011 (with a sound bite from Professor Gregory Wray, among other interviewees).

2. According to Judge Arms,”[t]he term ‘junk DNA’ was coined in the early 1980s.” In fact, the phrase normally is attributed to Susumu Ohno, who used it in the title of a 1972 paper [2]. Ohno did not reason that “we don’t know what noncoding DNA does, therefore, is it is useless junk.” Indeed, he proposed that the duplication and inactivation of genes produce non-protein-coding DNA (now designated pseudogenes) that might have a function. A video introducing Ohno and reading an excerpt from the paper about the role of the noncoding sequences as “spacers” with evolutionary importance can be found at Since 1972, other possible functions for noncoding DNA have been proposed. Some functions imply that the sequences should be conserved as one species evolves into another. Others, such as Ohno’s suggestion that noncoding sequences act as buffers between genes, do not.

3. See [5, p. 228] (referring to “a brief debate in the legal literature” necessitated by “a misunderstanding by Simon Cole over some of the things I [John Butler] had written in a review article on STR markers” and emphasizing that “STR markers used for human identity testing do not predict disease.”). One source of confusion, which also infects the Abernathy opinion is the thought that a statistical association between a locus and a disease detected in a family study in say, Northern India, establishes that the same association exists throughout the population in the United States.

4. Even a strong association (large relative risk) would not make for a useful predictive test if the prevalence of the condition is very small. See [3].

5. The sentence “[t]he relative risk of developing schizophrenia associated with this marker is small but it is not zero” is technically flawed. A relative risk of 1 would express a 0 correlation.

6. Replication is always important, and the problem of false positives is especially acute with genome-wide association studies. See, e.g., [6, 7].


1. State v. Abernathy, No. 3599-9-11 (Vt. Super. Ct. June 1, 2012).

2. S. Ohno, So Much “Junk” DNA in our Genome, 23 Brookhaven Symp. Biol. 366 (1972) (also published in Evolution of Genetic Systems 366 (H.H. Smith ed. 1972).

3. David H. Kaye, Please, Let’s Bury the Junk: The CODIS Loci and the Revelation of Private Information, 102 Nw. U. L. Rev. Colloquy 70 (2007).

4. David H. Kaye, Mopping Up After Coming Clean About “Junk DNA”, Nov. 23, 2007, available at

5. John M. Butler, Advanced Topics in Forensic DNA Typing: Methodology (2012).

6. D.J. Hunter & P. Kraft, Drinking from the Fire Hose–Statistical Issues in Genomewide Association Studies, 357 N. Engl. J. Med. 436 (2007).

7. Thomas A. Pearson, & Teri A. Manolio, How to Interpret a Genome-wide Association Study, 299 J. Am. Med. Ass’n 1335 (2008).

8. David H. Kaye, The Double Helix and the Law of Evidence (2010).

Cross-posted to Forensic Science, Statistics, and the Law.