The University of North Texas, Denton, has developed a drug sniffing car and a portable unit that fits in a pelican case.  The car can sample air quality while driving down the road and alert the driver to the chemical signature of say a meth lab. Several right turns later and the location can be isolated.  A portable unit can narrow the field down even more.

Cue the ACLU, the Black Helicopter crowd and conspiracy theorists everywhere on one, two, three OH SHIT, OH DEAR! 

But for Associate Justice Antonin Scalia this scenario might have come to pass. However in 2001 Justice Scalia wrote the majority opinion in Kyllo v United States. I am going to eliminate all the heavy lifting but by all means read the decision for yourself. In that the decision the court decided the use of technical means from outside a residence to determine if criminal activity was occurring inside the residence required a search warrant. Kyllo had an indoor marijuana grow operation that was discovered by a Forward Looking Infra Red (FLIR) mounted in a helicopter. The FLIR would show the heat generated by the grow lights and heat putt off by the plants.

Being one of the first kids on the block to use FLIR and a thermal imaging camera I wrestled with how that equipment could be used legally.  I even did a tag team with an Assistant United States Attorney (AUSA).  We tried to write a search warrant to authorize a FLIR overflight.  We presented our efforts to a more seasoned AUSA who observed that we did indeed have probable cause to use a FLIR.  His question was, “Why would we want to just look at the dope (a marijuana grow) when we had ample probable cause to knock the door down and seize the dope.  It took four years for Scalia’s words to penetrate my thick skull. Using technical means to see what is going on in a protected place is the same as if the police effected entry.  In either case they needed probable cause and a search warrant.

Here is the story out of Denton, Meth-Detecting-Cars-Chewing-Gum. The device can detect the odors or odor profile associated with methamphetamine manufacture.  By setting up a grid search the origin of the odors can be pin pointed.  The way I read Kyllo police might be able to drive around with the device activated, but as soon as the urge to make four consecutive right turns takes hold, the unit would have to be turned off.  I am not an attorney but I believe that Kyllo would preclude the next step of narrowing the area to be searched.

I base this on my experience with  a helicopter mounted FLIR.  The camera set at a wide angle could show every house in a subdivision.  A house with a high heat signature would leap out on the screen.  By changing the magnification the operator can focus in on the one house that represents an anomaly. But to throw the switch, the operator would have to have a search warrant, signed by a judge, based on probable cause. Anything less and the evidence would be inadmissible.

There are areas where there exceptions to the search warrant requirement where this device may have a use. It might have a use on the highway, monitoring traffic.  It would certainly have a place at ports of entry. 

This article represents a lesson to be learned and applied anytime new technology is bandied about as the newest cure.  It works fine in the lab, but can it be duplicated at a reasonable cost for real world use?  Are there societal, legal or moral prohibitions that would preclude it’s use?  I don’t expect the scientists at North Texas State to be familiar with nuances of search and seizure law.

Justice Scalia anticipated this development fifteen years ago.