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Tracking. Image courtesy of Shutterstock
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GPS tracking counts as a “search”, says US Supreme Court

The court sided with an offender who argued that being forced to wear a location monitor for the rest of his life is unconstitutional.

Tracking. Image courtesy of Shutterstock

Torrey Dale Grady is a repeat sex offender who has finished serving time in US prison.

Grady isn’t disputing the court’s assertion that he’s a recidivist sex offender.

But he has been battling North Carolina courts that have declared that he must wear a GPS ankle bracelet and thus be monitored via satellite by the government 24 hours a day, asserting that it constitutes unreasonable search and seizure and thus would violate his Fourth Amendment rights.

On Monday, the US Supreme Court sided with Grady.

In a unanimous decision, the justices affirmed that if the government attaches a GPS tracker to you, your car, or any of your personal effects, it counts as a search and is therefore covered by the Fourth Amendment.

The highest court in North Carolina had decided that wearing a tracking bracelet is no search at all.

In its succinct 5-page ruling on the case, Torrey Dale Grady v. North Carolina , the court scratched its head about that decision:

The only theory we discern ... is that the State's system of nonconsensual satellite-based monitoring does not entail a search within the meaning of the Fourth Amendment. That theory is inconsistent with this Court’s precedents.

…and thus sent the case back to the court that had dismissed Grady’s appeal.

The Supreme Court went on to cite precedents, the number of which have been growing right along with the proliferation of devices that feature geolocation tracking.

To wit:

  • In United States v. Jones, the Supreme Court decided that the installation of a GPS device on a suspect’s vehicle, and then monitoring that vehicle’s movements, constituted a Fourth Amendment search.
  • It reaffirmed that principle in Florida v. Jardines, where it held that having a drug-sniffing dog “nose around” a suspect’s front porch was a search, “because police had ‘gathered … information by physically entering and occupying the [curtilage of the house] to engage in conduct not explicitly or implicitly permitted by the homeowner.”

In his petition to the Supreme Court, Grady had complained that, because the monitoring bracelet has to be charged daily, he’s required to be plugged into a wall outlet at least once a day for 4 to 6 hours at a time.

Given that installing a GPS on a vehicle and having a dog sniff a porch were both considered to be Fourth Amendment searches, in that they are means by which the government seeks information, it stands to reason that slapping a GPS monitor onto somebody’s body would be as well, the court said.

From Monday’s decision:

In light of these decisions, it follows that a State also conducts a search when it attaches a device to a person's body, without consent, for the purpose of tracking that individual's movements.

As The Atlantic notes, this case doesn’t do much to clarify how the Fourth Amendment jibes with digital technology, including GPS data from mobile phones, which can triangulate location from nearby cell towers, or electronic toll-collection systems like E-ZPass that register, by default, a car’s location and when it passed through a toll road.

Rather, previous decisions concerning GPS data have focused on cases in which location data was collected by a GPS tracker employed by law enforcement.

Jennifer Lynch, a senior staff attorney at the Electronic Freedom Foundation (EFF), told the magazine that the Supreme Court seems well aware that they’ll soon have to grapple with whether the Fourth Amendment protects geolocation from, for example, our own phones.

But Monday’s ruling will at least force lower courts to consider whether attaching a GPS tracker to someone – which is how multiple states track sex offenders, requiring convicts to wear a location monitor for the rest of their lives – is a reasonable search, she said.

She thinks that it is not, and that it constitutes unwarranted punishment on people who’ve already served their time in jail:

They should have the opportunity to rebuild their lives and not be under a state of government surveillance for the rest of their lives, and that’s what a GPS tracker constitutes. Sex offenders - it’s the easiest class of people to place these kinds of punishments on, but I worry that we start with sex offenders and then we go down the line to people who’ve committed misdemeanors.

Image of tracking courtesy of Shutterstock.


I agree totally with the SJC decision, however why is it that the likes of Google, Yahoo, Facebook, and a whole host of other social media “track” you via your cell phone or I-pad or GPS. The “approval” in the citied case is definitive, but there is at most mere tacit” approval to these forms of “a search” when the consumer is either unaware of the total capabilities of the tracking by the device and how many times it is used by the company.

I would suggest that 90% or better of all consumers who buy a smartphone have no idea they are being tracked nor are they supplied an ‘advise and consent” that is clear and definitive as the SJC observed with the state.

I ask which is more an egregious violation of one’s 4th Amendment right to privacy? The state demanding and therefore advising the subject that he must wear a tracking device or tracking you without your knowledge at all???

I think the latter is more than the former most intrusive and it further “shares” the data for whatever it sees fit with other related and unrelated companies for a profit.


Nicely and concisely stated Enrique. Something that should be of concern to all of us. Unfortunately I think too many people today are unconcerned about sharing their data conciously or unconciously or consider it too much of a bother to check what their devices are “sharing”.


If the sex offender agreed to the GPS device as a condition of parol an early release from prison then the decision is right. If not then there could be a case. I sometimes think we probably don’t get all info on these stories.


The North Carolina case involves a non consensual search, the constitutionality of which is subject to Fourth Amendment protection, whereas the Google, et al tracking is a private matter and thus a contractual matter between the parties.


I should have been clearer, re: 4th amendment Vs. one’s own right to privacy.
I agree with all that the 4th Amm. applies to the actions of the government. Although the North Carolina example was “non consensual” the party had total knowledge that he was being tracked via the device application on his body, whereas the general public does not.

Strangely, the companies that do track us become nothing more than a mere extension of the government’s ability to track us. I think that this has already been shown to have been abused (in some people’s opinions) where the government would simply send a “stinger” msg to a cell phone locate an individual without a subpoena. Now a subpoena is required, nothing much more than a phone call and a paragraph as to why, to a DA and/or an AUSA.

By virtue of the tracking by Google and others the government does track you and everyone else that owns a device or automobile. The difference is they just have to simply “ask” the company for the data thus by “extension” the limits of the 4th Amendment are starting to get a bit blurry for me????

before I forget, I love the articles and such that appear on Naked Security…well done Sophos.


Should have added that the N.C. case involves a state action, which implicates the fourth amendment while a private matter does not.


“Terms and Conditions” are almost always agreed by users of services without reading them. Often they are padded out to be as long as a Shakespeare play, and life would grind to a halt if we were to read them all. There should be a limit of two A4 pages, beyond which the public should not be bound by the contents.


I think if you tried to impose a limit of two A4 pages, there would be a lengthy legal debate about what the equivalent length would be in Letter-size pages. Then a debate on the smallest margins allowed. Then about accpetable fonts and font sizes…

The problem I see with a statutory maximum length for a legal document of this sort is that, understandably, bigger and more complex products may have bigger and more complex conditions. Plus, there are so many jurisdictions in the world that trying to come up with two pages that address them all fully and frankly is hard.

(Ever tried to run a trivial competition in, say, Oz? Such as “sign up for our free white paper and enter into our draw to win a [modest prize],” which you’d think would be legally straightforward? Now try telling the public in one simple sentence what your lottery permit number is in each State and Territory.)

Why can’t the user decide? If there are more than two pages, don’t use the product or the service. Vote with your wallet!


So for recidivist criminals the choice then becomes, consent to the GPS anklets or stay in prison longer. Thats pretty simple. It’s there to protect other people’s right to feel safe, let’s not forget the victims.


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