Back in the day, if you got caught with a radar detector in VA, they took confiscated it. Turns out that was unconstitutional, "Illegal seizure" it was called.
I was reading a very interesting article about it on another forum, really opened my eyes about it.
From Radar Busters.com
"The use of a radar detector in a passenger vehicle is legal in all states with the exception of Virginia, Washington DC. and on military bases.
Laser Jammers and Radar Jammers are illegal in the states of Nebraska, Minnesota, Utah, California, Oklahoma, Virginia, Colorado, Illinois and Washington DC"
Laser jammers are emitting light, which is not regulated by the FCC, but can be regulated by the states.
A radar jammer (transmitter) that is powerful enough to blank a vehicle is actually illegal everywhere in the US, see the link below.
Technically the Federal Communications Act of 1934 states that you have the right to recieve any radio transmission that is out there. This was put into the act so that the government could not censor the airwaves, as was being done in some parts of Europe at the time. There is nothing in the act that exempts law enforcemet radars, radios or anything like that.
Here is the FCC public notice as to what you can and can't have as far as the Feds are concerned.
ftp://ftp.fcc.gov/pub/Bureaus/Mass_M.../da96-2040.pdf
So there is a federal law that says you can have a radar reciever. The state of Virgina can make it a crime to use it, but I don't think they want a court test case. Virginia was warned years ago by the FCC that confiscation of radio receivers (which is all a radar detector is) would subject the Commonwealth to federal charges each time they confiscate a detector, so they stopped doing it. The feds didn't want a case in federal court and the federal law is pretty clear. In some states the law was challenged based on the FCC Act, and some of the states rolled over before it could ever go to court. Virgina and DC are the only holdouts left.