Fight Crime with a Universal DNA Database?


DNA crime

Earlier this week, the New York Times ran a provocative op/ed by Yale law student Michael Seringhaus in which he advocated that the DNA profiles of every American be kept in a central forensic database. The goal of such a database is to help the police fight crime by better enabling them to find perpetrators who leave DNA traces at the scenes of their misdeeds. Current forensic DNA databases generally contain DNA profiles from convicts, but many states and the feds are now also including DNA profiles from arrestees.

Seringhaus thinks the current system is unfair because the databases are racially skewed. He also notes that the practice of familial searches which partial DNA matches can point to family members of people who already have their DNA on file, putting a criminal's family members under a cloud of suspicion although they have not been arrested nor convicted of any crime. Seringhaus is right when he notes that the DNA profiles can be used only for identification and does not reveal other genetic information provided that the DNA samples are destroyed once the profiles are digitally encoded. So what does he think are the advantages of a universal DNA database?

A much fairer system would be to store DNA profiles for each and every one of us. This would eliminate any racial bias, negate the need for the questionable technique of familial search, and of course be a far stronger tool for law enforcement than even an arrestee database.

This universal database is tenable from a privacy perspective because of the very limited information content of DNA profiles: whereas the genome itself poses a serious privacy risk, Codis-style profiles do not.

A universal record would be a strong deterrent to first-time offenders — after all, any DNA sample left behind would be a smoking gun for the police — and would enable the police to more quickly apprehend repeat criminals. It would also help prevent wrongful convictions.

As a practical matter, universal DNA collection is fairly easy: it could be done alongside blood tests on newborns, or through painless cheek swabs as a prerequisite to obtaining a driver's license or Social Security card. Once a biological sample was obtained, its use must be limited to generating a DNA profile only, and afterward the sample would be destroyed. Access to the DNA database would remain limited to law enforcement officers investigating serious crimes.

Since every American would have a stake in keeping the data private and ensuring that only the limited content vital to law enforcement was recorded, there would be far less likelihood of government misuse than in the case of a more selective database.

Interestingly, the American Civil Liberties Union is opposed to collecting DNA samples from anyone prior to conviction, specifically citing the problam of increasing racial disparities in the databanks. However, it would seem that Seringhaus' proposal for a universal DNA databank would obviate the ACLU's racial disparity argument. The ACLU is also worried that DNA samples might be used in ways that violate individual privacy, but once again, that objection fails if the samples are destroyed after the DNA ID profiles are encoded. The main ACLU objection is:

In America, people are presumed innocent until proven guilty. Thousands of people are arrested or detained every year and never charged with a crime. Housing a person's DNA in a criminal database renders that person an automatic suspect for any future crime – without warrant, probable cause, or individualized suspicion.

Law enforcement already has ample authority to collect a DNA sample from an arrested individual in those cases where a court-issued warrant supported by probable cause is first obtained.

But is DNA profiling all that legally different from fingerprinting? After all, the FBI's Integrated Automated Fingerprint Identification System (IAFIS) and the Department of Homeland Security's (DHS) Automated Biometric Identification System (IDENT) already contain the fingerprints of millions of people, both criminal and civil. Back in 2002, I noted:

The legislators and police argue that this expansion of DNA testing simply builds on a century's experience with ordinary fingerprinting. After all, obtaining a DNA sample with a cheek swab is not much more invasive than staining a suspect's fingers with ink, and it's a lot less invasive than alcohol blood testing or semen collection. According to this view, DNA testing is just another, perhaps more effective way to establish a suspect's identity and presence at a crime scene.

In 2006, in a column on using familial DNA searches, I predicted:

…that since collecting DNA is no more invasive than fingerprinting, it seems very likely that a similarly sized national DNA database will be created in the near future. And who knows—someday your genetic profile may be embedded in your national ID card too. Heck, who needs a national ID card if every cop has a fast DNA reader and wireless electronic link to the comprehensive national DNA database? If we want to avoid becoming a database nation, the time to stop it is now.

One final thought–by the end of this decade nearly everyone's physician will have a digital record of his or her complete genome on file. Here's betting that the police will regularly seek and get warrants to access the medical genome files of suspects by 2020.

Disclosure: I am still a member of the ACLU.