# Is it Illegal to Paint Your Car? **URL:** \ **Category:** Factual Questions\ **Created:** [January 25, 2008, 8:32am UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936 "2008-01-25T08:32:29Z")\ **Posts on this page:** 19\ **Page:** 2
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [January 26, 2008, 12:56am UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/21 "2008-01-26T00:56:06Z")
[QUOTE=human\_extinction] I’m pretty sure they do use IR. [/QUOTE] No. They are ordinary visible light cameras triggered by any of several methods, including radar, roadbed sensors and image-processing motion detection. ---
**Author:** ![J\_Cubed](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@J\_Cubed](https://boards.straightdope.com/u/J_Cubed)\ **Post date:** [January 26, 2008, 1:41am UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/22 "2008-01-26T01:41:04Z")
[QUOTE=Q.E.D.] Metal isn’t the only thing that reflects radar. Most materials can, to some degree or another. Even plastic and glass [/QUOTE] How well do humans reflect radar guns? Because even Wonder Woman has [problems](http://www.csfgraphics.com/blog_stuff/july17/diane2.gif). ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [January 26, 2008, 1:43am UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/23 "2008-01-26T01:43:09Z")
[QUOTE=J Cubed] How well do humans reflect radar guns? [/QUOTE] Much better than a baseball. Yet somehow, the majors manage to clock pitches with it. ---
**Author:** ![minor7flat5](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/minor7flat5/32/258_2.png) [@minor7flat5](https://boards.straightdope.com/u/minor7flat5)\ **Post date:** [January 26, 2008, 4:21am UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/24 "2008-01-26T04:21:33Z")
I am skeptical of those Mythbusters episodes that test ways of evading detection by the police. They did an episode on fooling radar detectors, one on fooling the breathalyzer test, and two episode on speed cameras. They disproved every trick they showed. But, this doesn’t mean that they exhaustively tried everything. The items they chose did not work. On top of that, this doesn’t mean they didn’t succeed with any product — they simply didn’t show it. They are making a television show. It must be entertaining, and they do edit lots of stuff out. Most importantly: they go through great pains to avoid ever showing explosives recipes or other secret products, so why would they show us “This is the one that actually busted the speed camera.” or “Yup, this one trick does fool the breathalyzer.” I think that there is a slight conflict of interest here, and that they would be pressured to not tell America exactly which product works perfectly for breaking the law. Every time I see them testing some way of getting around the law, I think to myself “Well, I know how this one is going to end.” Of course, now I’m remembering that they _did_ show how to fool a fingerprint scanner… Maybe my theory is bogus. I still think the pressure to suppress would be there. ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [January 26, 2008, 8:52am UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/25 "2008-01-26T08:52:43Z")
[QUOTE=gotpasswords] And as of the beginning of this year, the use and sale of those are illegal in California. Also illegal are the “fresnel” type license plate covers that are intended to obscure your plate: Specifically: But nothing saying you can’t paint your car whatever color you want, or even emulate a DeLorean and sand off all the paint. [/QUOTE] Yes, and CA passed a law against something which is absolutely useless in the 1st place. (It’s also illegal to own a “lipstick knife”, whatever the fuck that is. :rolleyes: ) ---
**Author:** ![Zabali\_Clawbane](https://avatars.discourse-cdn.com/v4/letter/z/ecd19e/32.png) [@Zabali\_Clawbane](https://boards.straightdope.com/u/Zabali_Clawbane)\ **Post date:** [January 26, 2008, 1:44pm UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/26 "2008-01-26T13:44:39Z")
[QUOTE=DrDeth] Yes, and CA passed a law against something which is absolutely useless in the 1st place. (It’s also illegal to own a “lipstick knife”, whatever the fuck that is. :rolleyes: ) [/QUOTE] Brass Knuckles Co. [lipstick knife](http://www.brassknucklescompany.com/CRE/lipstick-knife-p-299.html)? ---
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [January 26, 2008, 1:55pm UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/27 "2008-01-26T13:55:21Z")
[QUOTE=gotpasswords] Also illegal [in California] are the “fresnel” type license plate covers that are intended to obscure your plate… [/quote] I’m familiar with fresnel lenses, which are flat magnifying devices. How would a fresnel lens cover obscure a plate? ---
**Author:** ![Rhythmdvl](https://avatars.discourse-cdn.com/v4/letter/r/85f322/32.png) [@Rhythmdvl](https://boards.straightdope.com/u/Rhythmdvl)\ **Post date:** [January 26, 2008, 3:00pm UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/28 "2008-01-26T15:00:09Z")
[QUOTE=BobLibDem] The only requirement I know of regarding paint is that if you buy an old state police vehicle through the surplus auction, you have to sign an agreement that you’ll repaint it to be any color but blue. They don’t want bogus state troopers about. [/QUOTE] Um… forgive me if this was supposed to be a whoosh, but can you at least give us a state/country where that’s suspected to be the case? ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [January 26, 2008, 4:37pm UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/29 "2008-01-26T16:37:22Z")
[QUOTE=Musicat] I’m familiar with fresnel lenses, which are flat magnifying devices. How would a fresnel lens cover obscure a plate? [/QUOTE] If something is illegal, it doesn’t necessarily mean it works. ---
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [January 26, 2008, 4:48pm UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/30 "2008-01-26T16:48:35Z")
[QUOTE=scr4] If something is illegal, it doesn’t necessarily mean it works. [/QUOTE] OK, but what is the _fear_ that a fresnel lens would do? Make the letters large enough to read? ---
**Author:** ![si\_blakely](https://avatars.discourse-cdn.com/v4/letter/s/d9b06d/32.png) [@si\_blakely](https://boards.straightdope.com/u/si_blakely)\ **Post date:** [January 26, 2008, 5:50pm UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/31 "2008-01-26T17:50:40Z")
[QUOTE=Musicat] OK, but what is the _fear_ that a fresnel lens would do? Make the letters large enough to read? [/QUOTE] The non-magnifying fresnel makes it hard to read the numbers from any angle that is not straight on. Traffic Enforcement Cameras are off to the side of the road or above - an angle that makes it difficult to read the numberplate through the lens. Si ---
**Author:** ![Polycarp](https://avatars.discourse-cdn.com/v4/letter/p/82dd89/32.png) [@Polycarp](https://boards.straightdope.com/u/Polycarp)\ **Post date:** [January 26, 2008, 6:21pm UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/32 "2008-01-26T18:21:52Z")
[QUOTE=postcards] Back to the OP: One thing you may have to do is change the registration to reflect (pun intended) the new color. [/QUOTE] I was going to observe this, too. While I’m not sure it’s even a traffic infraction to drive a car with a different paint job than what’s specified, most if not all states have on the registration that plate SDM.B08 is issued to a _green_ 2004 Buick Fumebelcher, VIN C3C1LADA1115. Checking your registration and finding that you’re driving a **black** 2004 Buick Fumebelcher with that VIN plate hidden away wherever they’re secreting them these days is likely to be annoying to a cop. ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [January 26, 2008, 8:02pm UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/33 "2008-01-26T20:02:25Z")
[QUOTE=si\_blakely] The non-magnifying fresnel makes it hard to read the numbers from any angle that is not straight on. [/QUOTE] Non-magnifying? Then, I don’t know what it is, but it ain’t a Fresnel lens. ---
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [January 26, 2008, 10:55pm UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/34 "2008-01-26T22:55:44Z")
[QUOTE=si\_blakely] The non-magnifying fresnel makes it hard to read the numbers from any angle that is not straight on. Traffic Enforcement Cameras are off to the side of the road or above - an angle that makes it difficult to read the numberplate through the lens. [/quote] Never saw a non-magnifying fresnel lens. Maybe that’s some kind of fine grating that makes off-axis viewing difficult? ---
**Author:** ![si\_blakely](https://avatars.discourse-cdn.com/v4/letter/s/d9b06d/32.png) [@si\_blakely](https://boards.straightdope.com/u/si_blakely)\ **Post date:** [January 26, 2008, 11:16pm UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/35 "2008-01-26T23:16:23Z")
[QUOTE=Q.E.D.] Non-magnifying? Then, I don’t know what it is, but it ain’t a Fresnel lens. [/QUOTE] It’s not a real lens, but a set of clear concentric rings with different refractive indexes (air and plastic, or two plastics with different refractive indices). Light rays traveling straight through the “_lens_” go through a single refractive zone, and everything looks ok. Rays running through at an angle go through multiple refractive zones, hitting each one at a different angle (because they are concentric rings), and maybe even going through internal reflections at the transitions as well. You could even silver the transitions to increase those reflections. The effect is to distort the image from angles a few degrees off straight on, particularly in a fast shutter speed photo. It’s not a Fresnel lens, but it looks enough like one to confuse the layman. Si ---
**Author:** ![GuanoLad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/guanolad/32/42_2.png) [@GuanoLad](https://boards.straightdope.com/u/GuanoLad)\ **Post date:** [January 27, 2008, 2:07am UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/36 "2008-01-27T02:07:34Z")
I find the best way to beat a speed camera is to not speed. ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [January 27, 2008, 3:55am UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/37 "2008-01-27T03:55:21Z")
[QUOTE=si\_blakely] It’s not a real lens, but a set of clear concentric rings with different refractive indexes (air and plastic, or two plastics with different refractive indices). Light rays traveling straight through the “_lens_” go through a single refractive zone, and everything looks ok. Rays running through at an angle go through multiple refractive zones, hitting each one at a different angle (because they are concentric rings), and maybe even going through internal reflections at the transitions as well. You could even silver the transitions to increase those reflections. The effect is to distort the image from angles a few degrees off straight on, particularly in a fast shutter speed photo. [/QUOTE] Nice theory, but Mythbusters showed it didn’t work. ---
**Author:** ![Boozahol\_Squid\_P.I](https://avatars.discourse-cdn.com/v4/letter/b/d9b06d/32.png) [@Boozahol\_Squid\_P.I](https://boards.straightdope.com/u/Boozahol_Squid_P.I)\ **Post date:** [January 27, 2008, 10:42am UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/38 "2008-01-27T10:42:53Z")
[QUOTE=Rhythmdvl] Um… forgive me if this was supposed to be a whoosh, but can you at least give us a state/country where that’s suspected to be the case? [/QUOTE] When Maryland auctions off their state trooper cars, they remove the seal decal and the lights, but otherwise leave them looking the same. It caused me a lot of unnecessary I’m-driving-at-the-speed-limit-Officer! until I noticed the goofy teenagers or middle aged housewives at the wheel. ---
**Author:** ![si\_blakely](https://avatars.discourse-cdn.com/v4/letter/s/d9b06d/32.png) [@si\_blakely](https://boards.straightdope.com/u/si_blakely)\ **Post date:** [January 27, 2008, 1:47pm UTC](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936/39 "2008-01-27T13:47:13Z")
[QUOTE=DrDeth] Nice theory, but Mythbusters showed it didn’t work. [/QUOTE] I never said it would be effective in the real world. If it’s thin enough to avoid visual detection as a distorting device, then it probably is too thin to be effective, plus cheap plastic may not have the refractive qualities to produce enough distortion. Easier not to speed. Plus it won’t be long till they mandate RFID tags in the plates, making optical recognition systems unnecessary. Si [Previous page](https://boards.straightdope.com/t/is-it-illegal-to-paint-your-car/434936.md?page=1)