Technology moves so fast today that surveillance programs can now become routine before the public even learns of them. That is a problem because new surveillance programs can involve difficult value judgments and tradeoffs. How valuable are those programs in actually stopping criminals? How much privacy are we willing to give up for those benefits? What kinds of checks and balances do we think are necessary? In a democratic society, those are questions that should be answered not by law enforcement acting on their own as they install new technologies in the shadows — they should be decided by the people and their elected representatives after full democratic discussion and debate.

Know what a "hot watch" is? No? You're not alone. Until 2005, no one at any of the major civil liberties organizations did, either. That year, a government lawyer off-handedly mentioned that when the government orders a credit card company to disclose the time and location of a person's credit card purchases, it's called a hot watch. It's a way to track someone's location in real time — and as the lawyer explained, the government puts hot watches on people's credit cards routinely.

Hot watch is one example of a surveillance program that became routine before anyone knew it existed. Cell phone tracking is another. Law enforcement agents tracked the geographical location of suspects' cell phones for years without the public understanding they had this capability, let alone democratically debating how much power to grant law enforcement.

What other surveillance is going to become routine without any transparency or public debate? Today there are x-ray vans that can see through walls and clothing. We know little about which law enforcement agencies are purchasing these vans, or how they are being used. The same can be said about unmanned flying "drones" capable of aerial surveillance. While they have primarily been used by the military, they are so affordable now that even local law enforcement agencies have begun purchasing them with little or no public debate.

The lack of public information about surveillance is a problem because the United States is a democracy, and a core democratic value is that the people get to set the boundaries within which government operates. The rapid pace of technological change has made it difficult for people to understand, let alone make decisions about, the nature and extent of government surveillance.

Legislatures have an important role to play in exercising oversight of surveillance. In 1979 the Supreme Court ruled that law enforcement agents were free to obtain lists of the telephone numbers people dial, without any court involvement. Congress stepped in to protect privacy by passing a law requiring law enforcement agents to apply for a court order and assert the information is relevant to an ongoing criminal investigation.

Some may argue that secrecy is preferable because criminals will have a harder time evading surveillance they do not know exists. Eventually, however, word will get out and law enforcement's advantage over criminals will disappear. That temporary advantage is not enough to cast aside the democratic principle that new powers must only be given to the government with the consent of the governed.

Everyone recognizes that temporary and limited secrecy is sometimes necessary to protect the integrity of ongoing investigations. But when law enforcement adopts new surveillance technologies or techniques that impact personal privacy, the public should know about it, and should have a say in whether the benefits outweigh the costs.

(Originally posted on Open Salon.)

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