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Connecticut Resident Stopped By State Police For Radioactivity
Okian Warrior writes "A Milford, CT man was pulled over when a state police car radioactivity scanner flagged his car as being radioactive. The man had been given a cardiac exam using radioactive dye, and had a note from his physician attesting to this, but it raises questions about the legality of the stop. Given that it is not illegal to own or purchase or transport radioactive materials (within limits for hobbyist use), should the police be allowed to stop and search vehicles which show a slight level of radioactivity?"
You need more than just reasonable suspicion to get probable cause for a search. They are not the same thing.
http://en.wikipedia.org/wiki/Reasonable_suspicion
Reasonable suspicion is a legal standard of proof in United States law that is less than probable cause, the legal standard for arrests and warrants, but more than an "inchoate and unparticularized suspicion or 'hunch'";[1] it must be based on "specific and articulable facts", "taken together with rational inferences from those facts".[2] Police may briefly detain a person if they have reasonable suspicion that the person has been, is, or is about to be engaged in criminal activity; such a detention is known as a Terry stop. If police additionally have reasonable suspicion that a person so detained may be armed, they may "frisk" the person for weapons, but not for contraband like drugs. Reasonable suspicion is evaluated using the "reasonable person" or "reasonable officer" standard,[3] in which said person in the same circumstances could reasonably believe a person has been, is, or is about to be engaged in criminal activity; it depends upon the totality of circumstances, and can result from a combination of particular facts, even if each is individually innocuous.
http://en.wikipedia.org/wiki/Probable_cause
"Probable cause" is a stronger standard of evidence than a reasonable suspicion, but weaker than what is required to secure a criminal conviction. Even hearsay can supply probable cause if it is from a reliable source or supported by other evidence, according to the Aguilar–Spinelli test.
As a cardiac patient who has had isotope stress tests, and as a working chemist, let me state for the record that there is nothing "slight" about the level of radioactivity of a patient after one of these tests. Low level rad wastes, radioactive ores, uranium glass, all are slight levels of radioactivity, and measured as millionths of a Curie. The isotope used for stress tests is injected at 30,000 times higher levels, and the radiation emitted, gamma rays, penetrates through things like clothes, bone, muscle, and car doors.
The isotope used has a very short half-life so that two days after a test, there is very little radioactivity left, Right after a test a patient has a level of radioactivity that would scare the gloves off a rad-safety worker. If you point a Geiger counter at one of us, it doesn't click, it -whines-.
They pulled over a vehicle that was hot, and in other circumstances would represent a substantial safety hazard. More power to them.
Don't take life too seriously; it isn't permanent.
I'm going to blow a mod point and say those little white boxes are transmitters for a system of automatic weigh station check-ins and communicating with the driver whether or not he has to pull in to get weighed or if he gets to pass that station. http://www.prepass.com/services/prepass/Pages/WhatIsPrepass.aspx
I got nuthin
The interesting story here is state police cars with built in radioactivity detectors, obviously either checking for dirty radioactive weapons, nuclear weapons or newly arrived aliens hot off the star ships skulking about in their human skin suits ;).
Precisely. I did not know that. Not only built with radioactivity detectors, but ones that are on all the time and are damn sensitive if they are picking up the excess flux from a human inside a car from a tracer treatment administered presumably some nontrivial amount of time before from a distance of what -- 7 meters? 10? 20? -- while driving down the road. Tracers are often very short half-life elements -- that's why they use them -- lots or radioactivity but for a very short time. They tend to be produced in the hospital immediately before use and be mostly gone an hour or two later (but with an exponential tail). Clearly they nailed him right after he left the hospital, and he left the hospital rather quickly after the test, probably less than 45 minutes after the production of the tracer.
Are they sensitive enough to pick up a nuclear bomb being transported? Not if it is made with bomb-grade Uranium, which is also the easiest thing to make a bomb out of, but which isn't radioactive, although you might pick up the trigger. Plutonium 239 IS radioactive, producing a 5 MeV or so alpha at a rate sufficient to keep Plutonium warm to the touch, but alpha particles are relatively easy to block. It also typically contains Pu 240, which spontaneously fissions and produces a surplus flux of a few ~10 million neutrons per second from a typical core. Neutrons are more difficult to stop, but the intensity diminishes like 1/(4\pi r^2) so that the intensity at 10 meters is ~10^7/1250 or around 10^4 per meter squared per second. A detector as large as 1cm x 10 cm would then pick up 10 surplus neutrons per second at 10 meters, assuming there was zero attenuation in between and a perfect detector, neither of which is true. MAYBE this would give them signal to noise of a decibel or two, but given detector efficiency probably not until you were much closer. Up close it would be better, of course. Presumably their detectors have some sort of built in discriminator looking for sustained signal to noise above some cut-off.
What the patient was probably emitting is gamma. Gamma radiation has a long range and isn't easily blocked.
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Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.