look up laws in your state..google "(your state) radar detector laws"....radar JAMMMERS are illegal, but radar detectors are legal in almost every state except for like west virginia and a few others...BTW, get a Valentine 1 instead of the Beltronics STI, i have an older model STi and i love it, but i paid 50 for it...my cousin has the Valentine one and it is rediculously good