Supreme Court Rules that GPS Tracking Requires a Warrant

The U.S Supreme Court has ruled that the police cannot attach a GPS tracking device to a car without a warrant.

EDITED TO ADD (1/26): It seems I was wrong when I said that the ruling forces the police to get a warrant before placing a GPS tracking device on a car. The ruling is much more complicated and nuanced.

Posted on January 25, 2012 at 12:54 PM • 14 Comments

Comments

PhilipJanuary 25, 2012 1:07 PM

Unfortunately that doesn't seem to be accurate despite media reports. The case was decided on much more narrow grounds than that. The Court held that installing the GPS device was a 'search'.

Because the government's argument that they didn't need a warrant hadn't been raised properly in the lower courts SCOTUS never reached and decided whether a warrant would have been required or not.

See SCOTUSblog for a thorough legal analysis: http://www.scotusblog.com/2012/01/...

John JenkinsJanuary 25, 2012 1:12 PM

They ruled that it was a search, and therefore must be reasonable. A search with a warrant is presumed reasonable, but there are other occasions where a search is reasonable without obtaining a warrant.

DanielJanuary 25, 2012 1:16 PM

I agree Phillp. The press coverage is typical in how a lot of legal nuance gets lost in the shuffle.

My take is that there are nine members of the court who are deeply concerned by the challenges that rapid technological advances and the cultural shifts that accompany those changes and their impact on tradition 4th amendment legal analysis. On the other hand, there is no majority, let alone unanimity, on what a new analysis should look like. That's not surprising because there isn't any unanimity in American society as a whole.

In an ideal world this wouldn't even be an issue for the court to resolve. But the American people seem to have lost sight of the fact that the Constitution is an amendable document.

AlanJanuary 25, 2012 1:22 PM

An important but muddled decision--it only says that installation of a GPS tracking device is a search and did not decide whether or in what circumstances that search would require a warrant.

This is also an important and developing story about hard drive encryption:

http://www.cbsnews.com/...

AlanSJanuary 25, 2012 1:23 PM

Worth recycling the quote pulled out by Ohm from Justice Sotomayor's opinion:

"More fundamentally, it may be necessary to reconsider the premise that an individual has no reasonable expectation of privacy in information voluntarily disclosed to third parties. E.g., Smith, 442 U.S., at 742; United States v. Miller, 425 U.S. 435, 443 (1976). This approach is ill suited to the digital age, in which people reveal a great deal of information about themselves to third parties in the course of carrying out mundane tasks. People disclose the phone numbers that they dial or text to their cellular providers; the URLs that they visit and the e-mail addresses with which they correspond to their Internet service providers; and the books, groceries, and medications they purchase to online retailers. Perhaps, as JUSTICE ALITO notes, some people may find the “tradeoff” of privacy for convenience “worthwhile,” or come to accept this “dimunition of privacy” as “inevitable,” post, at 10, and perhaps not. I for one doubt that people would accept without complaint the warrantless disclosure to the Government of a list of every Web site they had visited in the last week, or month, or year. But whatever the societal expectations, they can attain constitutionally protected status only if our Fourth Amendment jurisprudence ceases to treat secrecy as a prerequisite for privacy. I would not assume that all information voluntarily disclosed to some member of the public for a limited purpose is, for that reason alone, disentitled to Fourth Amendment protection."

Fred PJanuary 26, 2012 9:42 AM

I agree with the comments above, although I think a lot of the press confusion is because there are few members of the press (legal press excepted) who both report on Supreme Court cases and have sufficient legal background to distinguish between relatively simple legal concepts.

One thing that was not brought up above, though, is that the opinions were highly suggestive of a majority in favor of classifying long-term monitoring as a search requiring a warrant.

However, that's a separate legal issue from attaching the device in the first place - that may well be a search not requiring a warrant; my reading was that there were at least 4 justices in favor of that view.

RHJanuary 26, 2012 1:22 PM

After spending a week slicing and dicing the term "Software Architecture," trying to pin it down to a definition which is usable, its comforting to see that our most highly venerated justices can spend 3 months and come out with nothing more than "GPS monitoring is a search."

I know everyone wants to see something more profound from them, but I, for one, am happy to see the Supreme court make the TINIEST ruling humanly possible before throwing the more specific issues back down into the lower courts. Small universal changes work better than large specific changes.

military intelligenceJanuary 26, 2012 2:11 PM

That's fine, they'll just chip you or spray you with a marking agent.

ScottJanuary 26, 2012 2:32 PM

Not sure how attaching a GPS is any different than having an officer follow the car. The contents of the car (and anywhere the car happens to be parked - in a garage, etc) are not transmitted, simply the location. I get that using UAV's the record video/audio from the 'protected' places would be a search, but this seems different to me. I mean, is it considered a search if a cop see someone enter their house, and then stands on the corner waiting for them to leave? don't think so.

Clive RobinsonJanuary 27, 2012 5:29 AM

First off there is a very great deal of difference between being followed by a human and having your vehicle or other possession tagged by a GPS tracking unit.

Importantly the human should be able to testify that "the person" being followed was in the vehicle or not, where as the GPS can only log where radio signals tell it, it's antenna is in three dimensional space and time, if and only if it can receive the signals directly from the satellites.

Thus the GPS provides NO EVIDENCE of a persons movments only where the GPS "RESOLVES" it's self to be. As we know GPS can be "spoofed" and it can be "relocated" onto another object.

The prosecution would therefore have to prove that,

1, The GPS had not been jammed or spoofed.
2, The GPS had not been relocated.
3, The GPS log was from the right device.
4, The GPS log was within "chain of custody" rules.
5, That the person was in/with the tagged object.

If the defence can show doubt on any of those points, then in an honest judicial process the evidence is not "beyond reasonable doubt" and it should not be used.

Now it is fairly easy to throw a bucket load of doubt into any system using either civil or military GPS alone...

As many will know GPSs does not work in many places such as "garages in/under houses", "multistory and underground car parks", "under some overhead power lines", "in some built up city/industrial areas"... Basicaly any where were the GPS suffers "Loss Of Signal" (LOS).

We also know that a GPS unit cannot tell the difference between LOS and "jamming" with Wideband Gausian Noise (WGN).

Thus, a switched on criminal could simply drive to some place known to cause LOS such as a carpark and whilst there turn on a GPS jammer and drive off. Provided they return to the same carpark before the jammer is turned off then the log shows the vehicle entering the carpark causing LOS, some time later the log shows AOS as the car leaves the same carpark.

So secondly, the GPS alone is not sufficient to say very much, it needs to be augmented in some way. And provided the criminal is aware of what the augments are they can take appropriate measures. The simplest being to just leave the vehicle in the car park and go catch some other form of transport whilst an accomplice goes "shopping" etc. However they also need to leave their phone etc with the accomplice, and remembering all this is the difficult bit...

Now the question arises as to how the criminal knows there is a GPS tag on any objects they associate with. All I will say (having gone trough it in the past on this blog) is look up a "Grid Dip Meter" or "Grid Dip Oscillator" it shows the prescence of "tuned circuits" at the selected frequency, and nearly all antennas for GPS units are effectivly "on frequency tuned circuits".

Thirdly and importantly the GPS does not provide any evidence as to what the person in/with the tagged object is doing. In the UK there was a case of a member of a local council who the police objected to joining the "oversight committee". After much back and forth the poice finally admitted that their objection was that his car registration had been recorded on successive Wednesday nights in a known red light district, therefore he was consorting with prostitutes. As it turned out he was having dinner with his sister who had the missfortune to have the road she lived in used by sex workers and their associates.

Humans unlike unminded objects are not always bound by Occam's razzor. In fact the opposit is true, a sutibly minded person can "game the system" the technolgy uses.

In London we have already seen this with gangs swapping clothing, mobile phones, travel cards etc. The simple fact is two people approximately the same hight wearing the same baseball cap, hoodie and sunglasses etc are very difficult if not impossible to tell appart reliably these days even with reasonable CCTV footage.

Importantly a gang also allows "ghosting" if you have six or seven people milling around at the bus travel (Oyster) card touch in point, it is quite possible for one of them to touch in twice with different travel cards thus one person has a "ghost companion" traveling with them. The person can also touch in for real and then under the cover of the gang slip out of the doors without it being recorded by the CCTV.

So GPS like most other "technical surveillance" measures is not realy of a lot of use against an aware and intelligent target, and can infact provide a clever criminal with support for an alibi...

ScottFebruary 2, 2012 11:29 AM

Clive, I agree that the effectiveness of a GPS device to track a suspect is, well, suspect. That fact does not in any way explain how using a GPS device to track a suspect constitutes a search anymore than 'tailing' a suspect constitutes a search. Whether the information that the device provides has any real value seems to be a very different argument.

Clive RobinsonFebruary 3, 2012 6:20 AM

@ Scott,

Sorry for a late reply Illness has struck again and I'm playing "catch up".

Ok so on with your question,

That fact does not in any way explain how using a GPS device to track a suspect constitutes a search anymore than'tailing' a suspect constitutes a search.

It's not obvious till you think sideways about it then it becomes a head slap moment.

Look at the difference between,

1, You unknowingly carrying a GPS in/on your person/possessions.
2, An LEO carrying a GPS in/on their person/possessions.

When you go off of "public property" into "private property" to which you have lawful access.

In case 1 the GPS goes with you, in case 2, the LEO is noot allowed onto the property withoout a search warrant etc. thus the GPS would remain off of the private property.

Now in Europe we have an expression for legal entities which is "Any Person Legal or Natural" which lumps companies etc in with individuals. US law likewise recognises certain legal entities as "persons" for company law etc to work. It is a fabrication which has a "legal nicety" about it.

The same logic can apply to LEO's and their agents, where the agent is "acting" "on behalf of" or "as a proxie to" the LEO, and the agent can be another person "natural" or "legal", where legal can also apply to a piece of technology.

Now as the GPS is concealed from you "you are unknowing of the agent" thus you are incapable of issuing an "invitation to it to enter the premises" thus as as an agent of an LEO it is restriicted in the same manner as the LEO is.

Otherwise the LEO could exceed their legal mandate by employing an agent, thus end running the law with regards to illegal searches and seizure which is enshrined in "being secure about their person and possessions".

Saddly it's a legal nicety, because if they put a GPS on your friend spouse etc and they (not you) know about it and you issue an invitation to them but not to the GPS then in effect it is a tort not a criminal act at best.

Which is why you get a problem with "knowing and unknowing" as long as it can not be shown that you became knowing the pretense of not invited remains. If hoowever the prosecution can show that your fingerprints or DNA etc are on the device then you have become "knowing" even if you don't know what it is.

However it's catch 22 because lets say you remove it and "dispose of it" in soome manner then in effect you have commited the crime of theft by denying the lawful owner the rights and priveledges pertaining to ownership...

You would then have to argue that the device was "gifted to you" or some such that you get ownership and thus the right to remove and dispose of the device.

One such way would be to put a notice on your possessions stating that anybody who adds to them either with or without your permission ceeds the right of ownership of the addition. But this in turn becomes a problem if somebody gifts you a bin full of manure through the open window of your car.

Now in the UK courts would have been much much less likely to entertain such arguments than in the US. Because in the past the person who was put under surveillance would be arguing against the Crown on the Crown's shilling (legal aid), where as in the US each side pays their own legal expenses, and in some respects the Judge as well which is oone of the reasons "electronic recods disclosure" is one of the new games in the legal vultures play book, because it can be used to bankrupt a small entity in various ways.

However it's nolonger an issue in the UK because during Tony Blair's reign as Prime Minister we got the Regulation of Investigatory Powers Act (RIPA) which got rid of the uncertainty of "named entities" putting other entities under surveillance without fear of prosecution or civil proceedings and then the ground work for the withdrawal of legal aid for such cases. And just to make sure that even the well heald cann't chalenge it either there is also the Proceads Of Crime Act (POCA) which rather than be used for the perpose outlined to Parliment (relieving mobsters and crime bosses of their ill gotten gains) has been primarily used to strip the assets of individuals as part of the time (dis)honered practice of "Striping an individual of their rights" because it removes an individuals access to their assets and thus prevents them from hiring legal help...

Thus the UK is well down the road of being a "hollowed out Nation" just like Mexico or Columbia or any number of countries where the notion of "justness" or "fairness" has been removed from the majority to protect the usually unelected minority.

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