Win For 4th Amendment: Court Rules Police Can’t Use GPS To Track Cars Without Probable Cause


A court has ruled that the secret placement of a global positioning system (GPS) device on a suspect’s car constitutes a search under the 4th Amendment, and that law enforcement cannot track suspects in such a manner without first obtaining a warrant based on probable cause.

On Tuesday, the 3rd U.S. Circuit Court of Appeals ruled, in a 2-1 opinion, that police cannot simply walk up to an unattended vehicle and plant a hidden GPS to be indiscriminately monitored for an unspecified period of time, with the anticipation that the vehicle will eventually be used in the commission of a crime.

Rather, the court found mobile GPS tracking to be a “vastly broader endeavor” than other forms of 4th Amendment searches — one that law enforcement cannot exploit through open-ended, warrantless surveillance of suspects who they assume will eventually do something illegal.

The appellate case in question, United States v. Katzin, illustrates exactly that. The American Civil Liberties Union (ACLU) provided a synopsis Tuesday:

In this case, police suspected three brothers, Harry, Mark, and Michael Katzin, of robbing several pharmacies. Without getting a warrant from a judge, FBI agents attached a GPS tracking device to Harry Katzin’s car in order to follow its movements. The government used the GPS device to track the Katzins as they drove to and from another pharmacy, and arrested them as they drove away. Before trial, the Katzins argued that police had violated their Fourth Amendment rights by using the GPS tracker without a warrant, and the district court agreed. Today’s ruling affirms that decision.

But the Court rejected the prosecution’s two arguments defending the warrantless GPS tracking.

The government had argued the police were legally entitled to track the car under an “automobile exception” carved out by previous legal precedents. But the Court repudiated that assertion, pointing out that the so-called exception arose from a case in which police performed a warrantless search of a parked car — not one whose movement could not be predicted, nor the future behavior of its owner accounted for. In other words, the police cannot “leave behind an ever-watchful electronic sentinel in order to collect future evidence” as they had done in the Katzin case.

The Court also spurned the government’s argument that the police involved in the GPS surveillance acted in good faith by adhering to the ever-changing environment, as they interpreted it, surrounding electronic surveillance law. In their opinion, the judges chided the police for their “Constitutionally reckless” behavior:

Where an officer decides to take the Fourth Amendment inquiry into his own hands, rather than to seek a warrant from a neutral magistrate — particularly where the law is as far from settled as it was in this case — he acts in a constitutionally reckless fashion. Here, law enforcement personnel made a deliberate decision to forego securing a warrant before attaching a GPS device directly to a target vehicle in the absence of binding Fourth Amendment precedent authorizing such a practice.

Personal Liberty

Ben Bullard

Reconciling the concept of individual sovereignty with conscientious participation in the modern American political process is a continuing preoccupation for staff writer Ben Bullard. A former community newspaper writer, Bullard has closely observed the manner in which well-meaning small-town politicians and policy makers often accept, unthinkingly, their increasingly marginal role in shaping the quality of their own lives, as well as those of the people whom they serve. He argues that American public policy is plagued by inscrutable and corrupt motives on a national scale, a fundamental problem which individuals, families and communities must strive to solve. This, he argues, can be achieved only as Americans rediscover the principal role each citizen plays in enriching the welfare of our Republic.

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  • Debbie Hogan Tate

    The only RIGHTS we have are those we are wiling to fight for!


    the cops are all corrupt!what is this,a tom cruz movie?
    if the cops want to do this,then we should have all the cops arrested,because we know they are all corrupt and they all will eventually commit a crime!

  • Mike T.

    I was arrested on a PPO violation on my own property which the person who had the PPO who lives 1/4 mile down decided to come out into the roadway & said i made contact with him. Went to court after 4 1/2 days in jail & the PPO was modified but the charges were not dropped. This is all from a neighbor who has een harassing us for 3 years now. I was mowing my grass at the time.