Your DNA uniquely identifies you with far more potential certainty than a fingerprint, because it is the chemical signature of your genetic makeup. And because technology has been developed to produce measureable quantities of DNA from as few as six skin cells, DNA testing has become a must-have tool in the toolbox of law enforcement agencies ranging from the county sheriff’s office to the FBI. Because DNA evidence is relatively easy to collect, even from unsuspecting suspects, it has proved invaluable in thousands of criminal cases, both to exonerate the innocent and to convict the guilty.
So why would anyone want to put any restrictions on the use of DNA for law enforcement? Prof. Erin Murphy, of the New York University School of Law, comes up with a host of reasons in a recent article in Scientific American. Most of them have to do with protecting the rights of innocent people, including the right not to be convicted of a crime you didn’t commit.
How could that happen, if DNA testing is so accurate? For one thing, the ideal precision of DNA testing assumes ideal conditions: a “clean” sample uncontaminated by the DNA of anyone other than the criminal, a perfectly conducted error-free laboratory analysis, and flawless record-keeping practices. In the real world of limited budgets, limited training, and messy crime scenes, none of these conditions can be guaranteed.
Murphy cites a research study in which researchers submitted the same samples to seventeen different DNA labs for analysis. Some labs said yes, the defendant was quite possibly the one who committed the crime. Others said in effect “No way!” So for whatever reasons, the results of DNA testing in that case were cloudy, to say the least.
Even if labs are run properly and samples taken carefully, DNA data contains a great deal more potential information about a person than the old-style fingerprints ever did. After all, DNA is the genetic code for making your body. It contains information about your sex, your heritage (which can often be interpreted in terms of race), and a host of other data which is only now beginning to be accessible through tests that are becoming easier and cheaper all the time. Murphy points out that it may soon be possible to screen DNA for a person’s potential to commit violent crime.
The last possibility raises the disquieting specter of predictive law enforcement. We have already seen what happens to those convicted of sex offenses with minors. Because there is a scientific consensus that recidivism in this particular population is almost 100%, such people are subject to the modern-day equivalent of Hester Prynne’s scarlet letter: they are prevented from living in certain areas, their addresses are matters of public record in many cases, and their civil rights are infringed to a degree that is unprecedented for most other types of crimes.
Nothing I have written exculpates sex offenders from their often heinous crimes. But the way we treat them sends the message that we hold the deliverances of science to be of far more importance and predictive power than an individual’s will or intent to reform.
It is not much of a stretch to imagine a future in which everyone, without exception, is required to submit a DNA sample to a nationwide database, much as you now have to be photographed to obtain a driver’s license. If experts develop a consensus that certain DNA data is a good predictor of the potential for violent crime, we could move well down the road to the creation of an instant criminal class whose only crime is being born with the wrong DNA. In some respects, that already happens with race, but at least most people admit that it is wrong for a law enforcement official to pull someone over merely for “DWB” (driving while black). If scientists and crime labs tell legislators that pre-emptively watching, or even locking up, certain people with certain kinds of DNA would lead to greater good for a greater number of people, the rights of those born with the wrong kind of DNA could be toast.
It can’t happen here, you say? In a society whose basic judgments of right and wrong are increasingly based upon nothing greater than the deliverances of the legal system, anything can happen if the lawyers and the judges say it can. And if such a system passed muster by the U. S. Supreme Court, we’d be stuck with it.
Murphy ends her article with a call for an accounting of the full costs, as well as the benefits, of the DNA database that government agencies have accumulated so far. While there is a widespread impression that DNA testing has been a boon for law enforcement, there are few studies that try to discover exactly what kinds of investigations benefit the most and what the overall error rate is when DNA evidence is used. Furthermore, she favors a ban against indiscriminate taking of DNA samples from persons who have not formally been charged with a crime. Because it’s so easy, some law enforcement agencies routinely take DNA samples from almost anyone they stop, whether they are charged or not. I agree with Murphy that these are probably unconstitutional “searches and seizures” that violate Article 4 of the Bill of Rights. Once again, the rapid advance of technology, this time in the form of inexpensive DNA testing, has outstripped the ability of the legal system to keep up with it, and to protect the rights of the general public against a small but determined cadre of officials.
DNA testing is truly a marvelous tool, but as with many other technological advances, it needs to be used with care. Now is the time to implement regulations and controls to ensure that the rights of both the innocent and the guilty are guarded from its improper use in the future.
Sources: Prof. Erin Murphy’s article “The Government Wants Your DNA” appears on pp. 72-77 of the March 2013 edition of Scientific American. In preparing this piece I referred to a Wikipedia article on the Houston DNA crime lab, which was shown to be in scandalous shape in 2003 in a series of news reports. It has since been reformed and obtained national accreditation a few years later.