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Home/Magazine Archive/November 2002 (Vol. 45, No. 11)/New Surveillance Techniques Raise Privacy Concerns/Full Text
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New Surveillance Techniques Raise Privacy Concerns
The Super Bowl is a sporting event deeply embedded in American culture. At the Super Bowl in January 2000, the police quietly began what may become a new tradition: the filming of spectators and the comparison of the taped images to a database of known criminals using advanced imaging technology. In such a way the police hope to be able to capture wanted criminals who would otherwise escape detection. This is the latest event in a recent trend of filming public places in the interest of public safety. Since Sept. 11, heightened security awareness has led to the introduction of sweeping new measures of which increased video surveillance is only one component. Using advanced digital image technology, filmed images are scanned for the likeness of known suspects using a computer. And while law enforcement officials laud the benefits of such techniques in capturing criminals, civil libertarians claim the use of such cameras also presents a serious intrusion on the right of the individual to privacy and anonymity.
To a certain extent, video surveillance has been used in public places such as subway stations and banks for decades. Until recently, such cameras would be monitored by a human being who would look for subversive or criminal activity. It was not possible to use a computer to draw conclusions regarding a recorded image, and as such this limited the appeal to law enforcement officials of filming public places.
The problems for a computer trying to identify a specific person from a photograph are many. People change their manner of dress and their hairstyles from day to day. The photo the police have on record may have a criminal unshaven, with glasses, and not smiling, while the surveillance camera may film the same criminal neatly trimmed, with contact lenses, and laughing. To identify these two images as the same without the aid of human analysis poses a daunting technical problem that has only been recently addressed.
There are several technological improvements that have made the Big Brother-type surveillance at the Super Bowl possible. For one, the quality of video images has improved vastly in recent years. As well, there have been theoretical advances in the development of complex mathematical algorithms that compare different images and look for matches. These algorithms have advanced to the point where they can still identify a person even if he or she has varied their appearance somewhat. And at the same time computers have become much more powerful and are more capable of performing the multiple complex computations these algorithms require. Together these developments have led to great advances in the field of so-called image processing used to identify a person in a photo.
These new digital image processing techniques combined with increased computing power and image quality have recently eliminated much of the requirement for human involvement in identifying a face in a photo. Suddenly it is possible for a computer to scan an image of a crowd, and check to see if a particular person is in that crowd. The potential of this technology in assisting the police in catching criminals is attracting the attention of law enforcement officials. This in turn raises the potential that a vast video surveillance network could monitor a wide range of our public lives.
In such a scenario, a centralized police computer could serve as a collection point for the video images. By continuously checking the recorded images against a database of known criminals, the computer could alert police when it detected a match. In the future, such a computer could also answer more complex questions of the sort: Was Mr. John Doe in the airport in the month of April? By comparing a photo of Mr. Doe with the digitized video recordings taken at the airport, the computer could then respond to this question.
As the technology of digital imaging matures further, the deployment of such cameras will only become more widespread.
Though this technology has yet to fully mature, the ability of computers to answer such questions is leading police and other organizations to install digital video cameras in a number of public places. This raises the complex issue of how much privacy citizens are willing to surrender in the interest of public safety.
There is little doubt that new video technologies can provide a powerful new tool in capturing dangerous criminals. For this reason, society has already become largely accepting of video surveillance at ATMs, government buildings, and other areas where security is a prime concern. To many, however, the recent deployment of video surveillance cameras in random public places is disconcerting. And as the technology of digital imaging matures further, the deployment of such cameras will only become more widespread.
There are other troubling issues related to video surveillance that privacy advocates would like to see addressed. Where are the filmed images stored, and who has access to the stored images? Video surveillance over the Internet is already a reality, so presumably an enterprising criminal could gain access to the recorded images and then use them for extortion. Also, the concept behind the video surveillance at the Super Bowl relied on comparing an image of the crowd with a database of photos of known criminals. Could this lead to the police maintaining a database with the photos of all citizens, criminals and innocents alike? And what would happen if the information in such a database fell into the wrong hands?
At this point it seems that technology is moving faster than public awareness and is outpacing the public debate. As well, the rush to introduce new security measures in the wake of the events of Sept. 11 has overshadowed privacy concerns. It may indeed be inevitable that the public will accept that it may be filmed at any point at any place, and that maintaining privacy will involve either a walk in the woods or wearing a mask. Civil libertarians, however, insist that any such acceptance be preceded by a vigorous public debate on the subject, in which society considers the delicate balance between maintaining law and order, and preserving the individual's right to privacy.
In the myriad of technological changes currently facing society and the host of accompanying ethical questions, such a debate has yet to seriously take place. Furthermore, the public's current willingness to sacrifice many aspects of privacy in order to combat terrorism may mean the debate on video surveillance will be put on the back burner. The danger is that by waiting too long there may be a de facto acceptance of the loss of privacy that will later be difficult to change.
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