has been a long held belief that owning and using a police scanner is illegal. The truth is that owning and using a scanner for use in your own home is legal, however, there are some things that are illegal to do with a scanner. In addition to Federal laws, local restrictions may apply and vary from state to state. For example, a few states require a permit or FCC amateur license for mobile scanner usage. Law regulating the use of radio scanners are enforced by the FCC (Federal Communications Commission) and spelled out in the ECPA (Electronic Communications Privacy Act of 1986).
The bottom line:
It is illegal to listen in on cellular and cordless phone calls.
It is illegal to intercept encrypted or scrambled communications.
It is illegal for scanner manufacturers to sell or import radio scanners that are capable of receiving cellular phone frequencies. (Note: This rule does not apply to sales by individuals and radio scanners made before 1985).
It is illegal to modify radio scanners so that cellular phone frequencies can be received.
It is illegal to use information you hear for personal gain. A common example is where a taxi driver listens to a competitor's dispatch channel for fare pick-ups and then races over and picks-up the fares.
It is illegal to use information you hear to aid in the commission of a crime.
It is illegal to disclose information you hear to other persons.
A full text copy of the Electronic Communications Privacy Act of 1986.
It may sound complicated, but don’t worry, if you are a law-abiding citizen and are not a convicted felon, there you should not have a problem.