Voodoo in a Box

In Evidence Class this week, my professor shared an interesting anecdote. He described a magical device called a "Contraband Detector" which could supposedly detect concealed drugs, cash, or weapons - pretty much whatever you wanted to find that a bad guy might be hiding.

The device was a scam, of course - just a box with some wiring in it and a little randomly fluctuating needle on the front. But, according to my professor, some cops bought it some officers even used it as a basis for their testimony in court: "We didn't find any drugs on the scene but we knew there was some there because the little black box told us so."

Anyway, my friend Dan thought he'd look into it further, and - I'll be damned - there is still a company out there selling this thing. Global Security Solutions is an Ontario based supplier of security, surveillance, and anti-terror supplies who proudly markets it on their website.

According to the description, the CDS-2002i can detect concealed "weapons, narcotics, alcohol, and explosives. As the suspect object is scanned, contraband materials reflect the low-level radiation, which is measured by the very sensitive detector."

This could be read two ways depending on how much charity you wish to extend to the folds at GSC: either totally bogus or semi-bogus.

Totally Bogus: If they mean that there are specific properties of contraband that this thing detects, this is just an outright scam. Is there something about not being allowed to have something that affects its physical properties? Will it detect nudie magazines under your son's bed?

Semi-Bogus: Of course, this could simply be a device to determine whether or not an object is solid all the way through. For example, you may want to know whether there is a bag of drugs submerged in a barrel of coffee beans, and maybe solid coffee beans reflect radiation differently than drugs surrounded by beans. I'd say this sounds more plausible except for the fact that they have a different product that does this using microwaves: The Advanced Contraband Detector.



If these things do anything at all, they probably just generate probable cause for searches. For every object you wanted to scan, you would have to have to scan an identical, contraband-free target to calibrate the device. Any detectable difference between your calibration target and the scanned object would raise suspicion regardless of whether it is the result of contraband, something allowable, operator error, or a poorly selected calibration target. The only way to tell the difference would be to perform a search. Perform enough searches, you will find some contraband. As long as you aren't being scientific about it (law enforcement generally isn't), selection bias might influence you to believe that the device is helping you find contraband, when in reality are just conducting random searches.

Note that GSC isn't just selling to small time suckers. They eagerly tout the fact that they are registered in the central contractor database to sell to the Defense Department and Homeland Security. I did a quick search and found that the Air Force bought a $20k "Surface Explosive Detector" from them in 2005, a device I couldn't find on their website. That's the only contract I found, but if they are making other sales as a subcontractor (a common practice), it wouldn't appear in my search. At any rate, lets hope taxpayers haven't foot the bill for too many dubious products.