US & Canada

Viewpoints: Supreme Court and DNA samples

Supreme Court Justice Anthony Kennedy speaking
Image caption Writing for the majority, Supreme Court Justice Anthony Kennedy said taking DNA is like fingerprinting

Two experts debate the Supreme Court's decision that police may routinely collect DNA samples during arrests to help solve old cases.

The Supreme Court says police may collect DNA samples during arrests to help solve old cases. Two experts examine the decision: one argues that their decision is justified; another says it is misguided.

Supreme Court justices stated that collecting DNA should be a routine procedure for police. In their ruling on the case Maryland v King, the justices said officials at all levels of government did not need a warrant to take DNA samples from any person arrested for a "serious" crime, to keep the information in a database and use it to solve cold cases.

Alonso King was arrested in 2009 and charged with assault. But a DNA test linked him to an unsolved rape case that occurred six years earlier. It matched semen taken from the rape victim.

King was subsequently tried and sentenced to life in prison without parole. The Supreme Court's decision over-ruled that by the highest court in Maryland, which said such DNA sampling had violated King's constitutional right to personal privacy.

Julian Sanchez, research fellow, Cato Institute

The Supreme Court has blessed the creation of a "genetic panopticon", as Justice Antonin Scalia describes the impact of Monday's decision.

Police may take DNA samples from people who have been arrested - but not convicted - and enter the information into a federal database without violating the Fourth Amendment's prohibition on "unreasonable searches and seizures".

Maryland's Court of Appeals set aside Alonso King's conviction on the grounds that collecting a DNA sample constituted a warrantless search unrelated to the offence for which he'd been arrested.

It was, in that court's opinion, no more legitimate than ransacking a drunk driver's home just to see whether he might be guilty of other crimes.

But the Supreme Court reversed that decision, reasoning that a DNA sample was just another means of "identifying" the suspect, akin to checking a driver's licence, or taking photographs and fingerprints.

Scalia's dissent makes it clear this is a pretext so thin it "taxes the credulity of the credulous".

King's DNA wasn't entered into the state's database until three months after his arrest when his assault case was well on its way to trial. There was no serious question of establishing his identity.

Justice Anthony Kennedy's majority opinion argues that "a person's identity" includes not just "what his birth certificate states", but "the whole context of who the person really is", including his "past conduct".

But that strained concept of "identity" amounts to a tacit admission that the true purpose of DNA sampling - on top of photo and fingerprint records - is not to identify people who are arrested.

Rather, as Scalia demonstrates, the point of this costly database system is to gather evidence for use in investigating unrelated crimes.

Moreover, since it would have been permissible to take a routine sample of King's genetic data after he was convicted of assault - at which point the same match would have been found - the point of collecting DNA from arrestees can only be to gather evidence from people who are not ultimately found guilty of whatever they're arrested for.

The database could easily grow to massive proportions if genetic sampling on arrest becomes routine: One recent study found that nearly a third of Americans are arrested for some offence by the age of 23.

Worse, because the court held in 2001 that police may arrest for infractions as minor as failure to wear a seat belt, Monday's decision will encourage pretextual arrests for trivial offences to evade the need for a warrant for genetic tests.

Nor can we take much comfort in the court's insistence that the DNA profiles entered into the federal database don't include enough information to reveal other sensitive information - such as family history, congenital medical problems or other genetic predispositions we may eventually be able to detect.

Image caption The Supreme Court ruled that police can collect DNA samples - which may be sent to labs for analysis

Once a genetic sample is collected, there is little in the Court's current Fourth Amendment precedent that would create an obstacle to running additional tests in the future - including, perhaps, tests yet to be discovered.

It's an unfortunate fact of the American legal system that nearly every Fourth Amendment case to reach the Supreme Court involves - as this one does - a criminal seeking to have evidence suppressed.

In the short run the court has succeeded in ensuring that one guilty man remains in prison.

The long-term consequence of that decision will almost certainly be a system of genetic surveillance encompassing millions of innocents - one whose full implications, as genetic technology advances, may take years to become apparent.

David Kaye, professor, Penn State Law

Not every state wants to establish databases of DNA from people who have been arrested.

Moreover, there is ample room to debate whether these databases would represent the best use of scarce resources.

But the US Constitution leaves the option open. This is the message from the Supreme Court today.

The dissenting justices on the court believe that the Fourth Amendment always prohibits suspicion-less entries into the body to investigate a crime.

These justices would brand these searches as "unreasonable" - no matter how minor the intrusion on the person or how much the programme advances the welfare of the public.

The dissent tartly concludes that "the proud men who wrote the charter of our liberties would [not] have been so eager to open their mouths for royal inspection".

Perhaps not. Yet if the only problem is the discomfort that comes from swabbing the inside of a cheek then a state could collect the DNA in another way.

The individual could, for example, place his fingers not just on a fingerprint card, but also on a sticky pad.

Ultimately, a more sensitive understanding of the Fourth Amendment is required.

It should be constitutionally reasonable to acquire, analyse and store biometric data without a warrant - and without individualised suspicion - under certain, limited circumstances.

Image caption At the Supreme Court, Justice Kennedy said collecting DNA is a "legitimate police booking procedure"

These might include when a person has been legitimately detained, for instance, and when the DNA collection is not overly invasive.

In addition, the collection of DNA should be done in an orderly manner - not following an arbitrary selection of individuals.

The biometric data should also be used only to establish the identity of an individual or to link individuals to crimes.

Fingerprinting of people who have been arrested satisfies these conditions. So does iris scanning and some forms of DNA collection.

The sticking point for many people is that DNA contains so much sensitive information.

That is surely a legitimate concern, and it is important that a system of collecting and analysing samples should have rigorous safeguards.

Image caption DNA, such as the sample shown here, is used to identify criminals

In this way, authorities can ensure that the samples collected are confined to biometric data - and carry no deep threat to privacy.

Unfortunately, the five justices in the majority engaged in what the dissent called "free-form balancing" - an approach that in other circumstances could be used in a way that would infringe upon important individual interests.

Although the dissent correctly perceived that the main purpose of the law is to investigate unsolved crimes rather than the true identity of an arrested person, the majority also pointed out the advantages of knowing whether a person who has been arrested is implicated in other crimes when making decisions about pre-trial detention.

At this point the clash between the majority and minority in the decision on Maryland v King leaves questions unresolved.

How long after an arrest must police wait before they can collect the DNA?

In Maryland authorities must wait at least until formal charges are read at a judicial proceeding known as an arraignment.

If the DNA of a person is similar to the DNA of an individual who has been implicated in a crime, can this fact be used to focus the investigation on his parents, children or siblings who might be full matches?

In Maryland authorities are not allowed to conduct these "familial searches".

Today the Court agreed that DNA samples taken when an individual is arrested "will have the beneficial effect of solving more crimes".

That much is clear.

Yet it is also clear, given the number of questions that have been raised, that the legislatures and courts are not finished with the constitutional and policy questions surrounding DNA databases.

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