Yeah I know this is an old and dead thread but it speaks exactly to what I am trying to determine.That depends on where you are, and what you're decoding.
In the USA, if it's a common carrier pager, it's illegal to decode anything but tone-only pagers.
As far as the law reads, it should be ok to decode a public safety agency's pagers IF they use their own frequencies rather than a common carrier to page. Not, of course, if they're encrypted, but no matter, if they are, you won't be able to, anyway. :roll:
Telling someone what you 'heard', whether from pagers or voice, is a seperate legal problem. Some will say it's ok now to 'reveal' police comms. The most recent court case posted here differed, and says it is NOT ok. The FCC currently seems to say it's ok to reveal. But they aren't the ones who'll prosecute. Your local US Attorney's reading of the law is what will, or will not, cause him to file charges.