The case went to the Supreme Court last November. At the time, we wrote:

Assigning a cop to tail every suspected criminal isn't physically possible, but that's no longer a problem with current trackers. "These devices—you put it on a car and leave it alone and check back in a month or two months or a year and have a record of where that person has been," [Cato Institute Fellow Julian] Sanchez says. "Is that something the Fourth Amendment would permit? And you intuitively want to say ‘no.’ "

The Court agrees. Justice Antonin Scalia wrote the opinion, saying that the government's decision to track Jones 24 hours a day—even on public roads—was still a search, and upheld the appeals court's decision that it was a violation of Jones' rights.

Photo by TexasGOPVote.com via Flickr/Creative Commons Attribution Generic 2.0 License

While MPD had a warrant to put a GPS tracker on Jones' car when it was in D.C., they opted to let the warrant expire, which effectively meant they tracked him without a warrant. He was then tracked 24 hours a day for a month.

The decision in this case will set precedent for whether it's okay for police to GPS track a suspect without a warrant, and whether they violate the Fourth Amendment of the Constitution (protection from unreasonable search and seizure) by doing so.

Libertarian privacy expert and Cato Institute research fellow Julian Sanchez talked to me about the case last month. Sanchez, who says it's "incredibly insane" that the conviction garnered Jones a life in prison sentence, adds that Fourth Amendment protections are most frequently "whittled down" by drug cases, because they are consensual criminal transactions. That is, the victim/buyer has no incentive to give up information.

But when the D.C. Circuit Court arrived at its decision to overturn Jones' conviction, it "cross-applied precedent" from a completely different area of the law, according to Sanchez. Which may get them into trouble. The court took the "mosaic theory," which has traditionally been applied to Freedom of Information Act requests, and used it to take Jones' side. This kind of "novel" approach to judicial rule-making is traditionally frowned upon.

The mosaic theory holds that using technology to track every moment in public—say, buying groceries, driving down 395, meeting a friend for a drink, etc—can add up to a violation of privacy since no one expects someone to track all of their public movements.

"The heart of this is that if your standard is 'what level of privacy do people reasonably expect?' then you have to grapple with the fact that people’s expectations are complicated," Sanchez says. "They expect to be seen, but not that any one person is following them around every day, all day, for a month."

The difference, then, is technology. Assigning a cop to tail every suspected criminal isn't physically possible, but that's no longer a problem with current trackers. "These devices—you put it on a car and leave it alone and check back in a month or two months or a year and have a record of where that person has been," Sanchez says. "Is that something the Fourth Amendment would permit? And you intuitively want to say ‘no.’ "

So which way will the court go on this? Sanchez says it's difficult to say. Most likely, he thinks they'll avoid making a big decision like supporting the use of the mosaic theory in this case, since it opens up a whole bunch of other issues.

Photo by TexasGOPVote.com via Flickr/Creative Commons Attribution Generic 2.0 License

City Paper interviewed Silverman and crew–as well as a few bystanders–outside the Dupont Circle Metro station as they handed out flyers informing riders that they have the right to refuse a search of their bags. One interview subject argued that the policy could lead to bigger and badder things, like security checks on the street–another subject said that happens already.

Having trouble viewing the video? Click here.

Metro announced the policy on Monday, Oct. 27, citing the 3rd District Court of Appeals ruling in MacWade v. Kelly as legal grounds for voluntary searches for security purposes. But the new-born policy has plenty of detractors, like Flex Your Rights, which seeks to inform citizens on how to "protect your constitutional rights during police encounters," and Students for Sensible Drug Policy, which opposes allowing transit police to use the searches as an opportunity to make unwarranted drug seizures and arrests. Even the Post's Robert Thomson–the man behind the Dr. Gridlock column–opposes  the initiative. Here's what Thomson (who could be seen speaking to Silverman outside the Metro this afternoon) had to say about the policy:

I've been riding Metro for 20 years and never had a reason to reconsider it until now. I'm not afraid to ride the trains. I'm afraid of giving up the rights that hundreds of thousands of Americans did die to protect over the past couple hundred years.

Since the transit authority and it's board chose not to discuss this with the public before implementing its random search policy today, it's difficult for me to offer you a clear statement of why they think you should give up your right to be secure in your property for a $1.65 train ride.

City Desk on the new policy here and here.