It is quite clearly a breach of the Radio Communications act
Section 133A unless LiveATC has permission to re-broadcast the transmissions. Being VHF (and therefore of limited range) the interception is taking place locally and this is where the breach of the law is occurring.
NZALPA care because the breach of law affects their membership (being controllers and pilots). It is all to easy to take or to use communication exchanges out of context and therefore misrepresent a situation.
As for the GCSB amendment if it is enough to wind up the NZ law society then it should be reason enough for us all to be concerned. Honest John's assurances just don't cut the mustard.
The fact this whole thing is getting thru with the assistance of 2 dodgy MP's (1 without even a registered party at the time and himself not willing to disclose the contents of his emails claiming privacy) smacks of arrogance and the railroading through of unsound legislation.