Thursday, July 21, 2011

The Great License Plate Kerfluffle

There has been a lot of press lately on a plan to increase the use of license-plate reading cameras by Massachusetts police. The state will pay for the equipment, on the understanding that the data will be shared with state and national law enforcement. The notoriously liberal town of Brookline, where I live, is tied up in knots over it (see the Globe), in part because the hated TV cameras already installed actually helped solve a horrible crime in Coolidge Corner a couple of years ago.

The issues are pretty straightforward: Are you more worried about the government tracking the innocent or about the possibility that a crime will unnecessarily go unsolved? As with all such tradeoffs, the analysis, to be done properly, needs some numbers. How big are the risks of abuse? How big are the chances of solving a crime by use of this data that would not have been solved without it? How big are the damages due to potential abuse? How big are the damages due to those unsolved crimes? The answer to the last question is "almost infinite, if the crime was against you or one of your family members." But how do you make policy out of that, even if you could come up with good estimates for the four numbers?

Harvey Silverglate is quoted in the Herald this morning in opposition:
“What kind of a society are we creating here?” asked civil rights lawyer Harvey Silverglate, who along with the ACLU fears police abuse. “There comes a point where the surveillance is so pervasive and total that it’s a misnomer to call a society free any longer.”
And it is hard to argue with that.  But what if the "surveillance" were done by ordinary citizens operating in public spaces?

License plate reading cameras are consumer commodities now. They cost a few hundred bucks. Here is one site with a lot of choices for you. There are many others. Fire up your shopping fingers and go to town.

What if we made the car-location database a crowdsourced project? A bunch of us buy these cameras and set them up outside our homes, aimed at the street. Logging every car that goes by and creating a database of license plate numbers and times of day at our location.

Then we share the data with each other and start to build up a city- or state-wide database. Or more likely, a peer-to-peer network of our individual databases so no individual has it all.

Of course, the database would not be as useful as what the police would have, because the index of who has which license plate number is not public information. But we could crowdsource that too. Make it a high school project -- have all the students walk around their neighborhoods and jot down the tag numbers of the cars parked in their neighbors' driveways. Better yet, give the Girl Scouts an extra badge if they collect this information as they go door to door all across America selling cookies. Such a database would be imperfect, of course, but obviously useful.

Disintermediation. We don't need the police any more to invade privacy; we can do it ourselves, particularly if we collaborate. If ordinary people can build Wikipedia, they can certainly build this database.

I have been thinking about this scenario for some time and I have no idea what to do about it. It shouldn't be against any laws to jot down the license numbers of the cars going down the street (when I was a kid trying to see all 50 states' plates, I was supposed to write down the actual number, not just the color pattern). Can't see why photographing them would be any different. Can't see why sharing information with my fellow citizens should be criminalized (now we're talking about my civil liberties). Ditto for writing down what is plain to see in public view, the street number of a house and the tag humber of a car parked in its driveway. If someone who knows more law than I do sees a logical leap in this reasoning, I'd love to know what it is. Perhaps this kind of data will be treated like nitrogen fertilizer--unregulated in small quantities, but heavily regulated in bulk. Would such a law about the private aggregation of mere facts pass Constitutional muster?

The first thing I said to Mark Zuckerberg (I still have the email) when he showed me the "Six Degrees to Harry Lewis" web site almost exactly seven and a half years ago was "It's all public information, but there is somehow a point at which aggregation of public information feels like an invasion of privacy." 

In 1998, in his book The Transparent Society,  David Brin asked a question which, updated to this particular scenario, would go like this: Would you rather live in a world in which the police have the location data for everybody's car -- or a world in which everybody has that data? 

My problem is, I don't see how to stop the latter transparent  world from evolving, unless we are prepared to limit other personal liberties (each individual's right to observe what is happening in public and to share that information with others). And at that point I have to conclude that we're not going to make the police the only people kept in the dark!