Federal Court of Appeals Holds that Police Need a Warrant to GPS-Track Your Car

Warren Buffett said in an interview recently, “If a cop follows you for 500 miles, you’re gonna get a ticket.”

Now, that’s a great line. And last week, in a different context, the Third Circuit Court of Appeals sounded a somewhat similar note when it held, quite logically, that if the government wants to attach a GPS tracking device to your car to spy on you wherever you go, it needs to get a warrant and show probable cause. The case is United States v. Katzin.

The Third Circuit covers Delaware, New Jersey, and Pennsylvania (as well as the Virgin Islands), but federal circuit decisions have persuasive force across the country and often shape law nationwide. For example, in 2010, the Sixth Circuit was the first in the country to hold that the government violates the Fourth Amendment when it accesses your emails without a warrant and probable cause. That decision has reportedly affected office-wide practice in several U.S. Attorney’s Offices around the country, though it has met with resistance in other quarters.

The law is evolving. As recently as 2010, the Ninth Circuit Court of Appeals, which covers California and several other states, held that attaching a GPS tracker to a car didn’t even constitute a search within the meaning of the Fourth Amendment. Then last year, the Supreme Court decided United States v. Jones and clarified that, yes Virginia, tracking a car like that was indeed a search; the Fourth Amendment was alive (if not well); and reports of its demise had been exaggerated (to mix a couple of cultural anecdotes). In a concurring opinion in Jones, Justice Samuel Alito sensibly based his reasoning on our reasonable expectations of privacy, observing that, until very recently, “society’s expectation has been that law enforcement agents and others would not—and indeed, in the main, simply could not—secretly monitor and catalogue every single movement of an individual’s car for a very long period.”

In the Katzin case, the Third Circuit said a couple important things. For one, the court denied that the “automobile exception” to the warrant rule applies to GPS tracking. As you may know, the longstanding automobile exception permits warrantless searches of cars because cars are mobile, and suspects can drive away with the evidence. But the court rejected its application in this case, explaining that the automobile exception was not intended to “permit [police] to leave behind an ever-watchful electronic sentinel in order to collect future evidence” without any judicial oversight.

Second, the court denied that the “good-faith exception” applied to absolve the government’s conduct. Under the good-faith exception, evidence obtained by way of a Fourth Amendment violation is not excluded at trial if the police relied on a reasonable, good-faith belief that the law permitted their conduct. The Katzin Court rejected that argument, however, even though the law was arguably unsettled at the time of the events in question.

The takeaway is that, when in doubt, we should err on the side of getting a warrant, rather than not getting one. Hopefully, other courts will follow suit.