13-3719. Obtaining wireless telecommunications services or wireless telecommunications devices fraudulently; manufacturing, distributing and selling unauthorized decoding devices; classification; definitions
I read through the entire thing, seems rather straightforward for most laws, it basically says that you are not allowed to use any device to gain unauthorized access to any radio, electronic, or telecommunications signal.
Anyone who's interested can go here to read the law in full.
I'm not exactly sure when this law was put in, but by the wording I think it was designed to prevent listening or capturing cell phone/wireless telephone communications....but it does go so far as to including electronic signals in the law.