The Latest Crime-Fighting Tool: GPS Devices

[BPSCG]

Someone was attacking women in Fairfax County and Alexandria, grabbing them from behind and sometimes punching and molesting them before running away. After logging 11 cases in six months, police finally identified a suspect.

David Lee Foltz Jr., who had served 17 years in prison for rape, lived near the crime scenes. To figure out if Foltz was the assailant, police pulled out their secret weapon: They put a Global Positioning System device on Foltz's van, which allowed them to track his movements.

Police said they soon caught Foltz dragging a woman into a wooded area in Falls Church. After his arrest on Feb. 6, the string of assaults suddenly stopped. The break in the case relied largely on a crime-fighting tool they would rather not discuss.

"We don't really want to give any info on how we use it as an investigative tool to help the bad guys," said Officer Shelley Broderick, a Fairfax police spokeswoman. "It is an investigative tool for us, and it is a very new investigative tool."

Across the country, police are using GPS devices to snare thieves, drug dealers, sexual predators and killers, often without a warrant or court order. Privacy advocates said tracking suspects electronically constitutes illegal search and seizure, violating Fourth Amendment rights of protection against unreasonable searches and seizures, and is another step toward George Orwell's Big Brother society. Law enforcement officials, when they discuss the issue at all, said GPS is essentially the same as having an officer trail someone, just cheaper and more accurate. Most of the time, as was done in the Foltz case, judges have sided with police. Link (http://www.washingtonpost.com/wp-dyn/content/article/2008/08/12/AR2008081203275.html?hpid=topnews).

[GreNME]

Since many new phones already have GPS devices in them, exactly how is this startling news?

I understand that there are weighty legal implications with planting a GPS device on a person's vehicle, though just the information from the article leaves me questioning how many of the details from the police side of things have been left out of the story. They'd have hellfire and brimstone raining down on them if certain legal protections weren't covered before applying the techniques described (or implied) in the article, especially in an area so close to DC (Fairfax and Falls Church).

[BPSCG]

I understand that there are weighty legal implications with planting a GPS device on a person's vehicle, though just the information from the article leaves me questioning how many of the details from the police side of things have been left out of the story. They'd have hellfire and brimstone raining down on them if certain legal protections weren't covered before applying the techniques described (or implied) in the article, especially in an area so close to DC (Fairfax and Falls Church).While my sense of this is that it doesn't run afoul of any Constitutional protections, I wonder why the cops don't ask for warrants. Presumably they have probable cause to want to follow a suspect around, and would be easily able to justify the warrant request to a judge. I doubt they're just sticking GPSs onto cars at random just to see what turns up.

[mrbaracuda]

Go GPS! :p

[GreNME]

While my sense of this is that it doesn't run afoul of any Constitutional protections, I wonder why the cops don't ask for warrants. Presumably they have probable cause to want to follow a suspect around, and would be easily able to justify the warrant request to a judge. I doubt they're just sticking GPSs onto cars at random just to see what turns up.

Yeah, if they're not using warrants then I agree there had better be some legal method or justification they're using. I know that when it comes to cell phones (particularly 911 calls) there is legal precedent, but I'm not sure what precedent they're using in the article.

[Darat]

While my sense of this is that it doesn't run afoul of any Constitutional protections, I wonder why the cops don't ask for warrants. Presumably they have probable cause to want to follow a suspect around, and would be easily able to justify the warrant request to a judge. I doubt they're just sticking GPSs onto cars at random just to see what turns up.

Yeah, if they're not using warrants then I agree there had better be some legal method or justification they're using. I know that when it comes to cell phones (particularly 911 calls) there is legal precedent, but I'm not sure what precedent they're using in the article.


In principle how is this different from good-old-fashioned following a suspect (for which I don't suppose the police need any warrants)?

[RadioactiveMan]

Hell, why don't they just mandate GPS on every new vehicle, and mandate installation on existing vehicles before they'll give you next year's tabs so they can track all of us all the time?

If there's no constitutional prohibition against following one guy with GPS, there shouldn't be any against tracking us all.

[BPSCG]

In principle how is this different from good-old-fashioned following a suspect (for which I don't suppose the police need any warrants)?Well, that's the police rationale; it does the same thing, only with less manpower.

Does the fact that the police are actually affixing the GPS to the suspect's car make a difference? Are they empowered to do that?

[RadioactiveMan]

Does the fact that the police are actually affixing the GPS to the suspect's car make a difference? Are they empowered to do that?
And what if you find the device and attach it to a squirrel? Are you empowered to do that?

[Darat]

...snip... Does the fact that the police are actually affixing the GPS to the suspect's car make a difference? Are they empowered to do that?

On the one hand my gut instinct is to be quite unhappy about this technological advance, on the more rational hand I am wondering how it is in principle different from what we have always empowered the police to do?

Just because you have to affix it doesn't seem grounds enough for it being that different from other surveillance methods - for example marking money to try and trace transactions criminals are making.

[Darat]

And what if you find the device and attach it to a squirrel? Are you empowered to do that?

Also don't see how that is in principle any different from trying to legally evade other forms of police surveillance?

[BPSCG]

And what if you find the device and attach it to a squirrel? Are you empowered to do that?
People have rights.
Governments are granted powers by people; governments do not have rights.

Anyway, what Darat said.

There's a scene in The da Vinci Code where Tom Hanks learns the police have surreptitiously dropped a tracking device in his jacket. He ends up tossing it into a garbage truck, throwing the police off his trail until the plot demands they catch up with him again.

[Francesca R]

Can one fight crime with a BPSCG device?

[RadioactiveMan]

Also don't see how that is in principle any different from trying to legally evade other forms of police surveillance?
Put differently: given that the tracker is government property, could you legally destroy it without consequence? Really, it's pretty much "abandoned" from your point of view, anyway...

[BPSCG]

Can one fight crime with a BPSCG device?Looks kinda big to surreptitiously attach to someone's car (http://www.batterseapowerstation.org.uk/gallery/exteriors.html).

But maybe it's not as big as it looks in the photos. Francesca, you're in the neighborhood - why don't you go have a look, and report back to us? :)

[Francesca R]

I am pretty sure that a lot of crime has been fought there in that case, if I recall (http://en.wikipedia.org/wiki/The_Professionals_(TV_series)) various (http://en.wikipedia.org/wiki/The_Sweeney) episodes (http://en.wikipedia.org/wiki/The_Bill) of these true stories.

[Bikewer]

I'm surprised there hasn't been any more legal weighing-in on this. Generally, police may use surveillance tools that are extensions of one's natural senses. Binoculars, for instance.
Helicopters and aerial surveillance falls into this category.

However, actually planting an electronic device on a suspect's vehicle would seem to go beyond this. I would think that this would require a warrant or court order, much as does wiretapping.
I would be surprised if this were not appealed on that sort of grounds.

[Rob Lister]

In principle how is this different from good-old-fashioned following a suspect (for which I don't suppose the police need any warrants)?

In my opinion, they should need a warrant to follow someone. Consider, if a 'civilian' did that to another 'civilian', they could be charged and [probably successfully] prosecuted with stalking.

I certainly admit that it's a gray line, but I think this is a very dark shade of gray.

I say 'nay', sort of like the knights that did the same.

[GreNME]

In principle how is this different from good-old-fashioned following a suspect (for which I don't suppose the police need any warrants)?
Also don't see how that is in principle any different from trying to legally evade other forms of police surveillance?

After a certain point in following a suspect there needs to be probable cause for the police to follow. For more manpower-related surveillance there does need to be a warrant in most cases. So, just using more conventional examples of surveillance, the GPS case would require at least a warrant with explicitly defined probable cause for it to fall under the realm of legality.

The problem arises when it comes to affixing the device to cars, which differs from more conventional means in terms of property rights and legality. Can someone have a GPS affixed to their car by the police, turn out to be innocent, and then file suit against the police if there was no evidence of a warrant to cover the documentation of probable cause? I don't know. I do know that it's somewhere in the realm of illegal for private investigators to use such methods, so I'd need to know what present statute is in place to allow it for law enforcement. I know that they probably exist (they do in other areas), but I would still think that such a statute would need to be in place for it to be legal for police while questionable (or illegal) for a private investigator.

[BPSCG]

For more manpower-related surveillance there does need to be a warrant in most cases. Really? I wasn't aware of that. Do you have a cite? It seems inconceivable to me that police can't just watch someone for weeks or months at a time without a warrant.

The problem arises when it comes to affixing the device to cars, which differs from more conventional means in terms of property rights and legality. Can someone have a GPS affixed to their car by the police, turn out to be innocent, and then file suit against the police if there was no evidence of a warrant to cover the documentation of probable cause? I don't know. That's kinda my issue with it (and anyone who knows me knows I'm no civil libertarian looney); may the police even touch your property without your permission?

[Darat]

Don't get me wrong I'm not arguing that it is right for the police to do this, it's just that I've not thought about it before so I'm trying to frame the issue by comparing it to what already happens and what procedures as a society we've been OK with so far.

(It's a bit like the complaint about privacy when we have cameras in public places - that isn't actually an invasion of a privacy we've ever enjoyed - it's just that the technology of cameras makes it more obvious.)

[The Painter]

That's kinda my issue with it (and anyone who knows me knows I'm no civil libertarian looney); may the police even touch your property without your permission?

If you're just out of jail and on probation, they do pretty much anything they want. They don't need a warrant for anything. They can just walk right into your house, car anywhere. If you are on probation, you have no rights.

[zooterkin]

Hell, why don't they just mandate GPS on every new vehicle, and mandate installation on existing vehicles before they'll give you next year's tabs so they can track all of us all the time?


You could do away with speed cameras, too, then...

[GreNME]

Really? I wasn't aware of that. Do you have a cite? It seems inconceivable to me that police can't just watch someone for weeks or months at a time without a warrant.

No cite on hand, but I can try to find you one later. It's often dependent on the situation and the kind of surveillance, in my experience (I am not a cop), but as far as I know once surveillance starts taking real man-hours (as opposed to watching something for like fifteen minutes) then there needs to be documented probable cause. Something like a patrol car driving up the street at regular intervals, however, circumvents that (and is common). What I'm not sure of is at which point it goes from a documented investigation to requiring a warrant, but with your example (watching for weeks at a time) my guess would be that there would need to be a location for placement of officers (or detectives) that would require something from a judge if the property owner (of the property being used, not the one being watched) didn't openly consent.

That's kinda my issue with it (and anyone who knows me knows I'm no civil libertarian looney); may the police even touch your property without your permission?

Police can enter an unfenced yard to a degree without permission, mostly for approaching the door of the house. However, police (and any municipal and probably federal law or code enforcement) may not enter a home unauthorized by either the property owner, the person living there, or a judge. The same applies to your car, but to a far lesser degree when on a road as opposed to in your driveway-- the reasoning is because on the road you are operating your property on city, state, or federal property, which means the whole probable cause assumption by an officer can carry more weight. Police still can't search your car without permission, but barring the car owner or operator giving permission police can get authorization to conduct a search very quickly.

That last part is where this issue seems tricky to me. I know that there is more leeway with law enforcement and motor vehicles that are driven on city, state, or federal roads, but my concern would be on how and where the devices were attached, and what level of probable cause is needed.

[Bikewer]

Don't even get me started on search & seizure....Soon we'll be talking about "curtilage" and other obfuscatory legal terms.

Again, I would be amazed if this process would withstand a court challenge. Essentially, it's electronic surveillance.

[Wides]

Don't even get me started on search & seizure....Soon we'll be talking about "curtilage" and other obfuscatory legal terms.

Again, I would be amazed if this process would withstand a court challenge. Essentially, it's electronic surveillance.

i agree. it does seem to be on the level of wire tapping.

[RadioactiveMan]

You could do away with speed cameras, too, then...
Well then, it's a win-win.

[BPSCG]

Again, I would be amazed if this process would withstand a court challenge. Essentially, it's electronic surveillance.

i agree. it does seem to be on the level of wire tapping.If it's so obvious that it wouldn't withstand a court challenge, then we should see a court challenge quite soon, shouldn't we?

I don't think it's obvious at all. I think it could go either way.

Some hypothetical questions that may help focus the issue:

If (or perhaps "when" is the better word) the technology becomes available to track a suspect wherever he is without physically touching him or his car, would that pass Constitutional muster? Say the technology becomes available for the police to simply catch a car on some kind of radar scanner, upload that car's unique identifying characteristics to a computer, which then uses a three-generations-from-now GPS satellite to monitor wherever that car goes, would that be okay? If not, why not?

If it would be okay, what makes the placement of the GPS device on the suspect's car unconstitutional? Is it the physical placement? If so, how is that significant?

As I hope I've indicated, I'm not certain this is a good idea, or, as one radio commentator remarked, "Catching criminals is a good idea; defending the Constitution is a better one." The fourth amendment is still the law of the land, and you have to ask at what point does the line get crossed from simply tailing someone to illegal search and seizure? If you may put a GPS on a guy's car, may you put a dust-speck sized one (three or four technological generations from now) in his pocket, or in his food? Before anyone cries "slippery slope," please understand that slippery slope arguments are not necessarily fallacious.

[ponderingturtle]

i agree. it does seem to be on the level of wire tapping.

Not quite, more on the level of getting phone records, with the added complication of it replaceing a person.

[GreNME]

BPSCG, I didn't forget your request, but I'm finding it difficult to give you an absolute. Apparently, the specifics of what level and how much leeway a law enforcement officer has varies and isn't always clearly spelled out in lots of places. I'm sure this is to allow for the ability of the officer to establish probable cause, but I'm also sure there are limits to this leeway as set forth by state and federal constitutions. For some better explanations than I believe I can give you, see if you can find "Criminal Investigation: A Contemporary Perspective" by Ronald Becker for more info. Chapter four discusses searches and seizures, including the warranted and warrantless types.

[BPSCG]

For some better explanations than I believe I can give you, see if you can find "Criminal Investigation: A Contemporary Perspective" by Ronald Becker for more info. Chapter four discusses searches and seizures, including the warranted and warrantless types.But surveillance isn't search and seizure. I'm sure a detective would have to justify to his superiors having a prolonged surveillance of a suspect, because of the time, money, and manpower implications. And if they wanted to stake out his apartment from the building across the street, they would certainly require the cooperation of the owner of that building. But I've never understood that they would need a warrant to conduct that surveillance.

Does the fourth amendment prohibit even touching a suspect's property in the process of a surveillance?

A suspect's car is clearly his property; does putting a GPS device on it amount to a search or a seizure?

Fourth Amendment:
The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.The police aren't searching the car or seizing it; they're just watching where it goes.


(I don't want to start another 2nd amendment argument, but I just noticed for the first time that the phrase "right of the people" appears there as well as in the 4th. It clearly applies to individuals in the 4th, but some gun-control advocates insisted, until recently, that it did not apply to individuals in the 2nd. Anyone who wants to discuss this should start another thread.)

[Alex Libman]

Yes another example of how technology ultimately becomes a tool of government tyranny.

[BPSCG]

Yes another example of how technology ultimately becomes a tool of government tyranny.Alex, if you think that there can never be any compromise between individual liberty and society's collective security, that every compromise of individual liberty in the interest of the welfare of society at large is an example of "government tyranny," could you please explain what the Preamble to the Constitution means by the language, "...insure domestic Tranquility, provide for the common defence, promote the general Welfare..." (bolding mine)?

After reading the first couple of paragraphs of the linked story, do you maintain that removing a sexual predator from the streets neither does anything to insure domestic tranquility nor does anything to promote the general welfare, but is instead an example of government tyranny?

[GreNME]

But surveillance isn't search and seizure.

Legally speaking, surveillance falls under the realm of search and seizure.

I'm sure a detective would have to justify to his superiors having a prolonged surveillance of a suspect, because of the time, money, and manpower implications. And if they wanted to stake out his apartment from the building across the street, they would certainly require the cooperation of the owner of that building. But I've never understood that they would need a warrant to conduct that surveillance.

Depending on the situation they absolutely would require one, and even under the best conditions a detective would require a legal documentation for surveillance of an individual beyond the realm of investigative profiling. The key here is the degree: following someone's car for a mile or so wouldn't be considered excess. Hanging out in a parked car near an entrance to an apartment building for an hour or three doesn't necessarily constitute an excess. Following someone's car across jurisdictions or spending shifts in a parked car or an adjacent empty apartment, however, will require greater legal justifications for two main reasons. The first is the possibility of infringing someone's right to privacy, and the second has more to do with the mismanagement or abuse of law enforcement resources (law enforcement agencies need to CYA as well).

Does the fourth amendment prohibit even touching a suspect's property in the process of a surveillance?

As far as I'm aware, it depends on the property and (again) what constitutes "touching" that property. Laying a hand on a car - probably not. Planting a listening or tracking device - I don't know for sure.

A suspect's car is clearly his property; does putting a GPS device on it amount to a search or a seizure?

Essentially, yes - it constitutes a search. This is where probable cause and documentation come into play to protect both the privacy of the individual and the integrity of a criminal investigation.

Fourth Amendment:
The police aren't searching the car or seizing it; they're just watching where it goes.

They're using the private citizen's property to search the individual's activities. Police patrols aren't legally allowed to follow specific individuals at random until they catch them going a couple miles over the speed limit or happen to be jaywalking, they are required to catch them in the act. Even if someone is under suspicion of being connected to a crime, they have a certain set of rights (both personal and property, hence my invoking it) protecting them from unwarranted surveillance. The trick, as far as I know, is warranting the level of surveillance with the appropriate probable cause-- meaning to a certain degree a professional assessment (suspicion) of probable cause is enough to warrant the surveillance, while to any degree past that requires more official documentation of probable cause.

However...

I'm not sure if using a planted GPS device on a car exceeds that degree. That's where I think the issue becomes murky, because there is a large gray and fuzzy area between following a car that is behaving suspiciously to entering someone's property in order to find a criminal or evidence of criminal behavior. Planting a GPS device, as far as I can tell, falls into that gray area somewhere and I can't quite pinpoint where. There's no absolute line of demarcation that I know of to plant it in the legal or illegal realm, and as far as I know there isn't any precedent yet in courts addressing it.

[Beanbag]

I suppose you could make the argument that the vehicle's in plain sight on a public road, clearly marked for identification with a license plate. Anyone with a pair (hell, even just one) of eyes can determine where it is and where it's going. No one has a reasonable expectation of anonymity on the road for their vehicle. Heck, even now, the government requires a buttload of identification-laden devices on my vehicle as it is -- license plates, inspection stickers, VIN numbers, plus a license to operate it and a card that says I'm insured. None of these are (currently) electronically-readable (with the exception of the license plates, which get scanned by the toll roads optically these days and the barcode strip on the inspection).

Still, there's that interesting case I heard but have never seen verified where an arrest was tossed out where a police officer used a thermal imaging scanner to look at a building where marijuana was suspected to be grown, and saw a heat image that looked like a bunch of grow-lights hanging from the ceiling. Court said "eyes only" on that one, and dumped the probable cause.

Beanbag

[GreNME]

I suppose you could make the argument that the vehicle's in plain sight on a public road, clearly marked for identification with a license plate. Anyone with a pair (hell, even just one) of eyes can determine where it is and where it's going. No one has a reasonable expectation of anonymity on the road for their vehicle. Heck, even now, the government requires a buttload of identification-laden devices on my vehicle as it is -- license plates, inspection stickers, VIN numbers, plus a license to operate it and a card that says I'm insured. None of these are (currently) electronically-readable (with the exception of the license plates, which get scanned by the toll roads optically these days and the barcode strip on the inspection).

We sign agreements with our state as to the level and degree of identification we are obligated to have present. To date, a GPS unit is not among them.

Still, there's that interesting case I heard but have never seen verified where an arrest was tossed out where a police officer used a thermal imaging scanner to look at a building where marijuana was suspected to be grown, and saw a heat image that looked like a bunch of grow-lights hanging from the ceiling. Court said "eyes only" on that one, and dumped the probable cause.

I've never seen such a case. Got an example? I've seen thermal imaging used in wooded areas and fields, but not buildings.

[BPSCG]

Still, there's that interesting case I heard but have never seen verified where an arrest was tossed out where a police officer used a thermal imaging scanner to look at a building where marijuana was suspected to be grown, and saw a heat image that looked like a bunch of grow-lights hanging from the ceiling. Court said "eyes only" on that one, and dumped the probable cause.Here it is (http://www.infoplease.com/cig/supreme-court/finding-marijuana-with-thermal-imaging-devices.html). Ruled 5-4 for the plaintiff. Interesting that Scalia wrote the majority opinion, while Stevens dissented.

[GreNME]

Here it is (http://www.infoplease.com/cig/supreme-court/finding-marijuana-with-thermal-imaging-devices.html). Ruled 5-4 for the plaintiff. Interesting that Scalia wrote the majority opinion, while Stevens dissented.

Excellent, thanks for the info.

I think the designation in that case of 'non-intrusive' might be useful for this issue. Could planting a GPS device on someone's automobile be considered intrusive or non-intrusive?

[BPSCG]

Excellent, thanks for the info.

I think the designation in that case of 'non-intrusive' might be useful for this issue. Could planting a GPS device on someone's automobile be considered intrusive or non-intrusive?I would think non-intrusive, since it isn't placed in the car, and it doesn't glean any information about what is happening inside the car, unlike the thermal detector.

FWIW, I think Scalia was looking down the road to the day that technology would allow police to be able to tell exactly what you're doing behind closed doors and sealed shutters in your house at any given moment. When that technology exists - and someday it will - you can't have police cars on routine patrol going down the street scanning people's houses for illegal activities.

[GreNME]

I would think non-intrusive, since it isn't placed in the car, and it doesn't glean any information about what is happening inside the car, unlike the thermal detector.

I'm not so sure it qualifies as non-intrusive. I haven't quite made up my mind on the subject, but it doesn't seem clear to me whether it's intrusive or not in either direction.

FWIW, I think Scalia was looking down the road to the day that technology would allow police to be able to tell exactly what you're doing behind closed doors and sealed shutters in your house at any given moment. When that technology exists - and someday it will - you can't have police cars on routine patrol going down the street scanning people's houses for illegal activities.

But could police cars attach GPS units to all of the cars on the street to check for illegal driving activities?

[jj]

Hell, why don't they just mandate GPS on every new vehicle, and mandate installation on existing vehicles before they'll give you next year's tabs so they can track all of us all the time?

If there's no constitutional prohibition against following one guy with GPS, there shouldn't be any against tracking us all.

Heck yes, just have them all phone home whenever anyone violates a speed limit by .001 mph, or runs a yellow light, or makes a bad turn, or leaves their lane, or anything else, too.

Leave the signals in the open,too, so anyone can see where anyone else's car is, any time. I mean, why not? What do you MEAN he stopped at the bar for 5 minutes on the way home. Go check his breath, and don't let him wash out his mouth, either. What? He stopped THERE? Check the car for porno, man, you might have a really killer bust there. He stopped on THAT street? Why, he's almost surely got pot in the car now! Quick! There? He stopped there? Why, his left wheels weren't off the pavement when he stopped at that fruitstand. Nab him! Fine the fruitstand!

Yeah, I mean, why not? You have nothing to lose if you obey the law, after all, do you?

Really, now, folks, electronic surveilance of any sort should absolutely require a warrant. That even goes for the contents of engine computers, etc.

[Wides]

Heck yes, just have them all phone home whenever anyone violates a speed limit by .001 mph, or runs a yellow light, or makes a bad turn, or leaves their lane, or anything else, too.

Leave the signals in the open,too, so anyone can see where anyone else's car is, any time. I mean, why not? What do you MEAN he stopped at the bar for 5 minutes on the way home. Go check his breath, and don't let him wash out his mouth, either. What? He stopped THERE? Check the car for porno, man, you might have a really killer bust there. He stopped on THAT street? Why, he's almost surely got pot in the car now! Quick! There? He stopped there? Why, his left wheels weren't off the pavement when he stopped at that fruitstand. Nab him! Fine the fruitstand!

Yeah, I mean, why not? You have nothing to lose if you obey the law, after all, do you?

Really, now, folks, electronic surveilance of any sort should absolutely require a warrant. That even goes for the contents of engine computers, etc.

Even though you have a bit a spooky Big brother extreme angle, you do have a good point.

[jj]

Even though you have a bit a spooky Big brother extreme angle, you do have a good point.

Exageration deliberate in this case. I don't expect 99% of any such thing. Just takes one, though, as far as I'm concerned, to ruin some poor sucker's life.

Even the "wheels on the road" thing has more consequences than most people want to admit in the modern day.

[Alex Libman]

Alex, if you think that there can never be any compromise between individual liberty and society's collective security, that every compromise of individual liberty in the interest of the welfare of society at large is an example of "government tyranny," could you please explain what the Preamble to the Constitution means by the language, "...insure domestic Tranquility, provide for the common defence, promote the general Welfare..." (bolding mine)?

The U.S. constitution wasn't talking about government spying on its citizens (which it clearly forbade), it meant keeping the Red Coats from re-invading, blockading, or sabotaging the new nation. This was the chief reason why the Federal government was created, remember?

"They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety." -- Ben Franklin

[BPSCG]

The U.S. constitution wasn't talking about government spying on its citizens (which it clearly forbade), it meant keeping the Red Coats from re-invading, blockading, or sabotaging the new nation. This was the chief reason why the Federal government was created, remember?Uh, no, it wasn't. It wasn't even a reason, let alone the chief one.

The reason the federal government was established was laid out very eloquently at the nation's founding, in its initial statement of principles:

We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness. That to secure these rights, Governments are instituted among Men...Bolding mine. That is the only purpose of any government. Period. Full stop.

Where the Declaration of Independence is the statement of principle (the "mission statement," in 21st-century English), the Constitution is the statement of the country's general rules by which it will attempt to implement the principles stated in the Declaration. The purpose of the Constitution is ...to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defence, promote the general Welfare, and secure the Blessings of Liberty to ourselves and our Posterity...Nothing in there about Redcoats.

Now, since you made the claim, could you please tell me where the Constitution prohibits spying on anyone?

Aside: Lord, I miss Shanek. There was a libertarian you could have an intelligent argument with. You'd actually learn useful stuff debating with him. One of those guys who put the "E" in JREF, as Darth Rotor likes to say.

[bpesta22]

could this be an invasion of privacy moreso than a search and seizure?

[SezMe]

While I agree that there is more than a little grey here, I finally come down on the side that it would require a warrant.

Suppose you opened the hood (bonnet for you guys over there :)) of your car to check the oil and found a GPS device. Would you feel that your privacy had been violated? If the GPS data were used in court, would you feel that you had been forced to testify against yourself? For me, the answers to both questions is a resounding "YES!"

To carry on with this scenario, suppose you smashed the GPS unit you found. Or suppose you hated your neighbor and put the GPS unit on his car. Would you then be liable for impeding a lawful investigation?

ETA: BPSCG, I agree with your point about Alex making one long for Shanek. With Shanek, one at least had a chance to learn something. The only thing I've learned from Alex is that his brain is hermetically sealed.

[RadioactiveMan]

We sign agreements with our state as to the level and degree of identification we are obligated to have present. To date, a GPS unit is not among them.
Really, though, that wasn't the point. The point was that on a public road, in plain view of anyone and everyone, you have no reasonable expectation of privacy regarding your travels. It would be rather like me slaughtering someone on my front porch, then griping about how witness testimony should be suppressed because they violated my privacy by watching me, even though I did it right in front of them.

Regardless, while I can't say with certainty this procedure violates the letter of the fourth amendment, I feel pretty comfortable in deciding it absolutely violates the spirit of the law.

[RadioactiveMan]

Here it is (http://www.infoplease.com/cig/supreme-court/finding-marijuana-with-thermal-imaging-devices.html). Ruled 5-4 for the plaintiff. Interesting that Scalia wrote the majority opinion, while Stevens dissented.
Unfortunately, a key component of Scalia's opinion rested on the fact that the thermal imaging technology was "not in general public use." So, when the day comes when FLIR is sold at Cabela's, there is a very reasonable chance that this specific opinion will be overturned, and our infrared emissions will be juicy for the observing. Any X- or gamma rays you may emit, however, should still be protected from warrantless observation for the forseeable future.

edit: It makes some sense, of course, to hing a little something on "general public use[age]" simply because we all have eyes and can use them to look for unlawful activity. However, it doesn't rest easy at all with me to consider the advance of technology and its ever-increasing availability to John Q. Public, then to consider the evaporation of any privacy rights we may have had because of science's indefatigable march forward.
/edit

FYI: While they may not be commonly sold at sporting goods stores, FLIR imagers can be picked up for less than five thousand dollars. The market saturation required for an item to be considered "in general public use" is unknown to me, but give it a few years...

[shadron]

It may also make a difference that there are two different sorts of GPS tracker units out there. The first one simply reads the satellite data and records the vehicle's position every, say, minute, and then is read back after being retrieved. The second form calls out on the cell phone service on its interval to place the position on a website so it can be actively monitored. Then, of course, there might be special law-enforcement types that communicate otherwise. After all, if the police are actively following the car around they have no need of GPS, a simple beeper do identify and allow for triangulation will do.

I do remember a case in California several years ago where a fireman (a professional arson investigator) was lighting fires in various places, generally using a simple fire bomb in furniture stores. When they started suspecting him they placed a beeper on his bumper, to see if he could be tracked to any stores that subsequently reported a fire. He came out of a 7-11 one day and saw the wire dangling down, and he removed the beeper. I remember that the beeper had a place in the trial, but I don't remember the outcome on that, except that he's now in the slammer for a while.

[GreNME]

Really, though, that wasn't the point. The point was that on a public road, in plain view of anyone and everyone, you have no reasonable expectation of privacy regarding your travels. It would be rather like me slaughtering someone on my front porch, then griping about how witness testimony should be suppressed because they violated my privacy by watching me, even though I did it right in front of them.

That's why I say it has less to do with the privacy argument than it does with the search and seizure argument at it's core. We are required on the road to be able to provide evidence that we have agreed to the terms and boundaries of the requirements by law for driving our auto on the road. Since the attachment of a GPS device is not part of those terms, it's not a matter or privacy but instead one of allowing lawful or unlawful search of our premises (our auto) despite meeting the other requirements we've agreed to in order to be privileged to drive on the road. Hence, does an arrest (seizure) using that search as evidence amount to a constitutionally legal action on the part of law enforcement?