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New police radars can 'see' inside homes

usatoday.com

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Re: New police radars can 'see' inside homes

#11

Post by gizmo686 »

baddox wrote: post #7
gizmo686 wrote: post #4

Earlier quoted context omitted.

Kyllo v. United States [1] Law enforcement used a thermal imaging camera to detect hotspots consistent with marijuana growth inside Kyllo's house. In a 5-4 decision, the Supreme Court ruled that this was a 4th amendment violation. [1] http://www.oyez.org/cases/2000-2009/2000/2000_99_8508

That's pretty close. I could see it going the other way just as easily.

In addition to the dissenting arguement being even weaker in this case, the Court gives considerable weight to precedent.

Re: New police radars can 'see' inside homes

#12

Post by [deleted] »

bjt2n3904 wrote: post #8
throwaway90999 wrote: post #3

Earlier quoted context omitted.

There's already been a ruling saying this isn't ok: http://en.wikipedia.org/wiki/Kyllo_v._United_States Kyllo was about thermal imaging but the opinion is quite clear. There's a much, much stronger case for thermal imaging equipment than there is for a device which probes via radio waves.

Just a few thoughts. Very simplistically... FLIR is a special camera that detects infra-red light. IR is electromagnetic radiation that is emitted from objects with heat. RADAR emits a more "traditional" radio wave, and then detects objects when the radio wave reflects back. Unlike FLIR (which is passive), I would consider RADAR to be active. I would think (rather naively so) that the case against using RADAR without…

[deleted]

Re: New police radars can 'see' inside homes

#13

Post by jonahx »

As disturbing as the police use is, I am more disturbed by the possibility (inevitability?) of devices like these, and similar audio devices, becoming so cheap and readily available that even basic privacy from strangers while in your home becomes a thing of the past.

It seems to me that before too long anyone could pick up audio and video devices for a couple hundred bucks that would allow them to see you in your own house and hear your every word.

Re: New police radars can 'see' inside homes

#14

Post by gizmo686 »

bjt2n3904 wrote: post #8
throwaway90999 wrote: post #3

Earlier quoted context omitted.

There's already been a ruling saying this isn't ok: http://en.wikipedia.org/wiki/Kyllo_v._United_States Kyllo was about thermal imaging but the opinion is quite clear. There's a much, much stronger case for thermal imaging equipment than there is for a device which probes via radio waves.

Just a few thoughts. Very simplistically... FLIR is a special camera that detects infra-red light. IR is electromagnetic radiation that is emitted from objects with heat. RADAR emits a more "traditional" radio wave, and then detects objects when the radio wave reflects back. Unlike FLIR (which is passive), I would consider RADAR to be active. I would think (rather naively so) that the case against using RADAR without…

One nice thing about the Supreme Court is that every ruling comes with at least one (or two if the ruling is not unanimous) experts explaining the situation. And if any of the remaining Justices disagree, or feel that something was left out, of those two opinions, they can add their own.

In this case, the dissent wrote:

    Unlike an x-ray scan, or other possible "through-the-wall" techniques, the detection of infrared radiation emanating from the home did not accomplish "an unauthorized physical penetration into the premises,"
and:

    While the Court "take[s] the long view" and decides this case based largely on the potential of yet-to-be-developed technology that might allow "through-the-wall surveillance," ante, at 38-40; see ante, at 36, n. 3, this case involves nothing more than off-the-wall surveillance by law enforcement officers to gather information exposed to the general public from the outside of petitioner's home. All that the infrared camera did in this case was passively measure heat emitted.
https://supreme.justia.com/cases/federal/us/533/27/

Re: New police radars can 'see' inside homes

#16

Post by comrh »

jzwinck wrote: post #10
femto wrote: post #5

Does the US use "sarking" [1] (metal foil insulation) in house construction? Most Australian houses are wrapped in a layer of metal foil insulation. Presumably that would offer some attenuation to radar, though the windows must still allow radiation though, as mobile phones typically work inside. Perhaps a house with metal foil based window tinting would offer a reasonably complete Faraday cage? [1] http://www.bradfo…

People use a lot of different construction materials and techniques across the country, but I don't think this "sarking" is common for residences. People don't want to live inside Faraday cages though, for the reason you already mentioned: their mobile phones wouldn't work. Not to mention broadcast television, AM/FM radio, garage door openers, etc.

I've thought about living in one, I only use radio in the car and TV comes in through cables. On the plus side my wifi would be protected from wardriving (or an outside access) as it would never leave the house.

Cell service would definitely be a problem though.

Re: New police radars can 'see' inside homes

#17

Post by dhughes »

What if it's passive? Wifi from the routers of homes emit the RF energy and all the police do is use a detector I could see that as legal since it's energy being emitted just as if it were light shining out a window and you were a silhouette.

http://www.extremetech.com/extreme/133936-using-wifi-to-see-...

>The system, devised by Karl Woodbridge and Kevin Chetty, requires two antennae and a signal processing unit (i.e. computer), and is no larger than a suitcase. Unlike normal radar, which emits radio waves and then measures any reflected signals, this new system operates in complete stealth.

Re: New police radars can 'see' inside homes

#19

Post by userbinator »

jzwinck wrote: post #10
femto wrote: post #5

Does the US use "sarking" [1] (metal foil insulation) in house construction? Most Australian houses are wrapped in a layer of metal foil insulation. Presumably that would offer some attenuation to radar, though the windows must still allow radiation though, as mobile phones typically work inside. Perhaps a house with metal foil based window tinting would offer a reasonably complete Faraday cage? [1] http://www.bradfo…

People use a lot of different construction materials and techniques across the country, but I don't think this "sarking" is common for residences. People don't want to live inside Faraday cages though, for the reason you already mentioned: their mobile phones wouldn't work. Not to mention broadcast television, AM/FM radio, garage door openers, etc.

The response of materials to EM radiation and its attenuation is highly frequency-dependent (at the very high frequencies, this is why we see things having different colours), so it doesn't have to be all-or-nothing; a material could be transparent to most frequencies but appear opaque to the ones radar use - essentially, the filter absorbs all the energy at particular wavelengths.

http://en.wikipedia.org/wiki/Notch_filter http://en.wikipedia.org/wiki/File:Atmospheric_electromagneti...

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