Worried that government is using new technology "to collect information about all of us, all the time, and to store it forever, providing a complete record of our lives for it to access at will," the ACLU filed information requests in 38 states and Washington, D.C., and found something alarming (emphasis added):
Automatic license plate readers are the most widespread location tracking technology you've probably never heard of. Mounted on patrol cars or stationary objects like bridges, they snap photos of every passing car, recording their plate numbers, times, and locations. At first the captured plate data was used just to check against lists of cars law enforcement hoped to locate for various reasons (to act on arrest warrants, find stolen cars, etc.). But increasingly, all of this data is being fed into massive databases that contain the location information of many millions of innocent Americans stretching back for months or even years.
Here's a nifty explainer they put together:
It wasn't so long ago that privacy rights advocates were cheering a Supreme Court decision in United States v. Jones that put limits on law enforcement's ability to place GPS trackers on cars. With enough license-plate readers on the street, all feeding into a centralized database, the government could forgo GPS trackers and the Fourth Amendment tests that they trigger, and just monitor all cars always, plugging in a license plate when they want to know about the bygone movements of a particular person. In other words, advances in license-plate reader technology are just one more reason that Justice Sotomayor was correct when she mused, in her concurrence, that SCOTUS' current approach to the Fourth Amendment offers inadequate privacy protection.
Awareness that the Government may be watching chills associational and expressive freedoms. And the Government's unrestrained power to assemble data that reveal private aspects of identity is susceptible to abuse. The net result is that GPS monitoring--by making available at a relatively low cost such a substantial quantum of intimate information about any person whom the Government, in its unfettered discretion, chooses to track -- may "alter the relationship between citizen and government in a way that is inimical to democratic society."
I would take these attributes of GPS monitoring into account when considering the existence of a reasonable societal expectation of privacy in the sum of one's public movements. I would ask whether people reasonably expect that their movements will be recorded and aggregated in a manner that enables the Government to ascertain, more or less at will, their political and religious beliefs, sexual habits, and so on. I do not regard as dispositive the fact that the Government might obtain the fruits of GPS monitoring through lawful conventional surveillance techniques. I would also consider the appropriateness of entrusting to the Executive, in the absence of any oversight from a coordinate branch, a tool so amenable to misuse, especially in light of the Fourth Amendment's goal to curb arbitrary exercises of police power to and prevent "a too permeating police surveillance."
More fundamentally, it may be necessary to reconsider the premise that an individual has no reasonable expectation of privacy in information voluntarily disclosed to third parties. This approach is ill suited to the digital age, in which people reveal a great deal of information about themselves to third parties in the course of carrying out mundane tasks.
Driving down the street, I have no reasonable expectation that my license-plate number won't be jotted down by someone. But I am aghast at the notion that it could be recorded on all major streets, at all times, with each scan aggregated in a massive database and stored forever. I'm confident that the men who wrote and ratified the Fourth Amendment would be similarly aghast. The technology is here, and increasingly being used.
There isn't much time left to stop it.