The Supreme Court asks whether the government can put a GPS device on your car without a warrant.

Antoine Jones was convicted in 2008 and sentenced to life in prison for possessing and conspiring to distribute more than 50 kilograms of cocaine. Key evidence in the case against him was obtained in 2005, when District of Columbia police got a warrant to secretly install a GPS device in order to monitor the Jeep Cherokee driven by Jones and his wife. The warrant expired after 10 days, but the police nevertheless used the GPS to monitor everywhere he drove, every 10 seconds, for 28 days. He led them to his “stash house” in a Maryland suburb, where they found powder and crack cocaine, plus $850,000 in cash. Jones tried to have his conviction set aside, arguing that warrantless GPS surveillance violated his Fourth Amendment right to be free of unreasonable government searches and seizures. The government replied that GPS tracking is no different from police observing activity in public spaces and roadways, which is not protected under the Constitution.

A panel of the D.C. Circuit Court of Appeals ruled last August in favor of Jones, finding that the government may not conduct protracted, around-the-clock GPS surveillance without a warrant. Judge Douglas Ginsburg, writing for the three-judge panel wrote that "the police used the GPS device not to track Jones' movements from one place to another, but rather to track Jones' movements 24 hours a day for 28 days as he moved among scores of places, thereby discovering the totality and pattern of his movements from place to place." Other federal appellate courts have agreed with the government that one has no expectation of privacy in activity open to public view on city streets.

Now, I know what you’re thinking: Given all the recent discussion of the extracurricular activities of Supreme Court justices, and their failure to disclose participation in various secret and/or partisan events, isn’t a GPS affixed to judicial vehicles kind of a great idea? Doesn’t America have a right to know where the justices go when they go places?

Chief Justice John Roberts (Metro station, kids’ school, Metro station, kid’s school) is way ahead of you, my friend. One of his first questions to Deputy Solicitor General Michael Dreeben this morning is just that: Would it constitute a “search,” he asks, “if you put a GPS device on all of our cars, monitored our movements for a month?”

Dreeben swallows and then asks carefully: “The justices of this court?” Then he starts to say that the justices driving on public roadways have no greater expectation of privacy than anyone else—but the chief justice stops him. “So you could tomorrow decide that you put a GPS device on every one of our cars, follow us for a month—no problem under the Constitution?” Well, no.

Justice Samuel Alito (ballgame, American Spectator dinner, ballgame) is a prodigious worrier about new technology and privacy. He puts it this way: “Most of the privacy people enjoyed was not the result of legal protections or constitutional protections, but the difficulty of traveling around and gathering up information. But with computers, it's now so simple to amass an enormous amount of information about people that consists of things that could have been observed on the streets.”

Then it’s time for Justice Ruth Bader Ginsburg (opera, opera, Aspen Institute, opera, elephant) to express her reservations. “The government's position would mean that any of us could be monitored whenever we leave our—our homes,” she says. “Is the end point of your argument, that an electronic device, as long as it's not used inside the house, is OK?”

Dreeben clarifies that the issue here is “monitoring somebody's movements in public. We are not talking about monitoring their conversations, their telephone calls, the interior of their cars, their private letters or packages.” Which sends Justice Stephen Breyer (Renaissance Festival, Omega Quadrant) into something of a Stanley Kubrick tizzy, asking about 1984 and “futuristic scenarios.”

Dreeben says there is no distinction to be drawn between a 1983 case in which the Supreme Court found no Fourth Amendment violation when cops affixed a “beeper” to a chemical container in the suspect’s truck. But that case involved a single car trip. In Dreeben’s view, “Under a principle of law that says one trip is OK but 30 trips is not, there is absolutely no guidance for law enforcement.”

Roberts suggests that a GPS is worrisome because it gives the government a massive of amount of information. Dreeben replies: “So does a pen register, so does a garbage pull. So does looking at everybody's credit card statement for a month.” But the court doesn’t deem those searches. Justice Anthony Kennedy (Salzburg, Berlin, Czechoslovakia, Russia, China, England, Greece, Wales) wonders whether the government can affix a GPS device to your overcoat. Justice Sonia Sotomayor (baseball game, Bronx, Manhattan) tells Dreeben that under his theory of the case, “You could monitor and track every person through their cellphone, because today the smartphones emit signals that police can pick up and use to follow someone anywhere they go. … They have no reasonable expectation that their possessions will not be used by you … to track them, to invade their sense of integrity in their choices about who they want to see or use their things!”