More to the point, I wonder if the Police have the proper certification to use these devices at the general public. I mean, with all the hoo har about Mobile Phones causing cancer and other claptrap, radars should be in the same boat.. And lasers, they'll cause permanant blindness if theyre shone in your eyes.
I've discussed this with a few mates of mine too. Its probably going to be MUCH easier to develop a device that tricks the radar into thinking youre doing some ungodly insane speed, like 800km/h than actually successfuly jamming the radar signals. Possibly combined with a radar detector, so it triggers off when youre actually being targeted.
Radar and laser speed traps take advantage of the doppler effect, listen to a V8 car driving past you. More to the point, listen to the engine note change just as it passes you. Anything emitting waves of anything that is moving is subject to the doppler effect. A radar speed device emits waves of a certain frequency. When it hits a car and bounces back, these waves become compressed. How compressed they are depends on how fast the vehicle is driving. So the more compressed they are, the faster the vehicle is going. If they aren't compressed, then the vehicle is stationary. So in order to dupe the radar device into thinking youre doing some insane speed, you just need to burst back some massively compressed microwaves. Then, when the copper pulls you over, you can claim his unit is busted, or his Daily Configuration Certificate is forged, etc.. Or that the flashless radar is out of order, how on earth can a Falcon do 800 km.h :D
BTW they use the doppler effect to judge how fast stars are moving away from us in astrophysics and other such intersting fields :)