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Judge Orders NYPD to Release Records on X-ray Vans

propublica.org

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Re: Judge Orders NYPD to Release Records on X-ray Vans

#11

Post by tightfleece »

munin wrote: post #4
tightfleece wrote: post #3

> "releasing the documents would hamper the department's ability to conduct operations and endanger the lives of New Yorkers." Then apparently the lives of New Yorkers are protected by security through obscurity, with absolutely no evidence of efficacy and absolutely no auditable evaluation of safety. I'm thinking that a strong education in science should be a requirement for anyone who touches these programs with a…

There's a difference between "secrecy" and "security", and when people complain about how releasing some information would hamper / endanger lives, they mean that some amount of secrecy is involved in protecting stuff. Computer nerds often don't understand Kerckhoffs's law this way. The security of a system should not be dependent on obscurity, but some amount of security will depend on secrecy, i.e. your private key…

According to Kerckhoff, "A [crypto]system should be secure even if everything about the system, except the key, is public knowledge."

If any amount of your security depends on hiding how the system works, you have a broken system (according to said law).

Nobody is arguiung that the van passcodes or personnel files should be disclosed; those specifics are immaterial. We are asking that how the system works, and how that is evaluated, be made public, and be placed under scrutiny. Otherwise, there is no reason to believe this system does anything but provide a vector for corruption.

Re: Judge Orders NYPD to Release Records on X-ray Vans

#12

Post by UnoriginalGuy »

They have a very interesting way of reporting radiation exposure (ditto with airport scanners). Instead of reporting the total body accumulated dose, they report the dose a single scanning beam sweep induces over a small area.

These machines use a tight beam (or several) which sweep. Each individual beam when measured in isolation likely deliver 0.1 microSievert of radiation. However the total body dose (accumulated dose) is significantly higher than that (because you'd measure the total dose delivered, rather than the total dose delivered to a small 1x1 square cross-section).

This is interesting because while the body can and does (continuously) repair DNA damage, it has diminishing returns. So 0.1 microSieverts to the entire body is totally inconsequential, however 0.1 * 100 or more? Particularly to people who are frequently scanned (or those with weakened bodies due to illness or age).

Plus these X-Ray means can and do bounce. So imagine three 1x1 cross sections, you scan the left and right, but the middle will have a measurable radiation exposure even if not directly exposed to the X-Ray beam (partly because the beams are imprecise but partly because of reflected X-Rays).

Honestly 0.1 μSv is the headline figure. What is the full body accumulated figure? I'm going to guess as much as .30 μSv per scan.

Re: Judge Orders NYPD to Release Records on X-ray Vans

#13

Post by pyre »

lifeisstillgood wrote: post #10

It seems the NYPDs argument is that releasing information on the vans will allow people to predict where they are (or more likely be told ala speed cameras) and so avoid them (civilians as well as criminals). That's kind of the point of a deterrent. You cannot scan every car on every journey, at least not without a massive spike in cancers, so this is a deterrent. And it's a secret deterrant.... So it won't catch any…

Reminds me of Dr. Strangelove.

  Dr. Strangelove: Of course, the whole point of a Doomsday
  Machine is lost, if you *keep* it a *secret*! Why didn't =
  you tell the world, EH?

Re: Judge Orders NYPD to Release Records on X-ray Vans

#14

Post by athenot »

UnoriginalGuy wrote: post #12

They have a very interesting way of reporting radiation exposure (ditto with airport scanners). Instead of reporting the total body accumulated dose, they report the dose a single scanning beam sweep induces over a small area. These machines use a tight beam (or several) which sweep. Each individual beam when measured in isolation likely deliver 0.1 microSievert of radiation. However the total body dose (accumulated…

Also, these scanners are not operated by trained radiologists, and I am highly doubtful that those who do operate them have been given adequate clinical training—much less care about the clinical ramifications.

Re: Judge Orders NYPD to Release Records on X-ray Vans

#15

Post by csbrooks »

UnoriginalGuy wrote: post #12

They have a very interesting way of reporting radiation exposure (ditto with airport scanners). Instead of reporting the total body accumulated dose, they report the dose a single scanning beam sweep induces over a small area. These machines use a tight beam (or several) which sweep. Each individual beam when measured in isolation likely deliver 0.1 microSievert of radiation. However the total body dose (accumulated…

"Honestly 0.1 μSv is the headline figure. What is the full body accumulated figure? I'm going to guess as much as .30 μSv per scan."

Should .30 be 3.0? Or...?

Re: Judge Orders NYPD to Release Records on X-ray Vans

#16

Post by kyleblarson »

tightfleece wrote: post #3

> "releasing the documents would hamper the department's ability to conduct operations and endanger the lives of New Yorkers." Then apparently the lives of New Yorkers are protected by security through obscurity, with absolutely no evidence of efficacy and absolutely no auditable evaluation of safety. I'm thinking that a strong education in science should be a requirement for anyone who touches these programs with a…

I would take that a step further. I think that a strong general education should be a requirement to work in law enforcement.

Re: Judge Orders NYPD to Release Records on X-ray Vans

#17

Post by psykovsky »

kyleblarson wrote: post #16
tightfleece wrote: post #3

> "releasing the documents would hamper the department's ability to conduct operations and endanger the lives of New Yorkers." Then apparently the lives of New Yorkers are protected by security through obscurity, with absolutely no evidence of efficacy and absolutely no auditable evaluation of safety. I'm thinking that a strong education in science should be a requirement for anyone who touches these programs with a…

I would take that a step further. I think that a strong general education should be a requirement to work in law enforcement.

Where I'm from it's mostly the bullies who get to join law enforcement...

Re: Judge Orders NYPD to Release Records on X-ray Vans

#18

Post by uxp »

tightfleece wrote: post #11
munin wrote: post #4

Earlier quoted context omitted.

There's a difference between "secrecy" and "security", and when people complain about how releasing some information would hamper / endanger lives, they mean that some amount of secrecy is involved in protecting stuff. Computer nerds often don't understand Kerckhoffs's law this way. The security of a system should not be dependent on obscurity, but some amount of security will depend on secrecy, i.e. your private key…

According to Kerckhoff, "A [crypto]system should be secure even if everything about the system, except the key, is public knowledge." If any amount of your security depends on hiding how the system works, you have a broken system (according to said law). Nobody is arguiung that the van passcodes or personnel files should be disclosed; those specifics are immaterial. We are asking that how the system works, and how th…

Additionally, the court is not asking for the schedule and routes of the vans to be released. Knowing where a security guard is at any given time is much more useful than knowing that security guard's name. I don't think that really falls under the obscurity part, but I could be wrong.

Re: Judge Orders NYPD to Release Records on X-ray Vans

#20

Post by k-mcgrady »

>> "The X-ray vans—which reportedly cost between $729,000 and $825,000 each—are designed to find organic materials such as drugs and explosives."

As much as I don't like this at least explosives are a good reasoning for using them. Drugs? Come on! Exposing citizens to radiation, no matter how little, so you can find people in possession of drugs is ludicrous. Every time you think the war on drugs has reached the height of stupidity they raise the bar even further.

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