Prof Kevin Clements and Prof Richard Jackson, of the university's National Centre for Peace and Conflict Studies, yesterday said proposed GCSB changes were being promoted as addressing a ''legal anomaly''.
But the proposal had ''worrying implications for individual privacy, civil liberties and national security'', they said.
''It provides expanded powers of surveillance without evidence of real necessity or effectiveness, or corresponding safeguards of individual liberty and privacy.''
The law change would effectively merge the Government Communications Security Bureau (GCSB) and the Security Intelligence Service (SIS) plus the intelligence wings of the military and the police.
This was moving New Zealand towards what was known as a ''national security state'', with intrusive surveillance capacity, challenges to freedom of speech, control of citizens and potential civil rights abuses.
''We do not think this critical law should be changed without more extensive public discussion about its potential costs and benefits.''
There were good reasons to keep the roles separate and the official oversight and authorisations required for
the SIS were much greater than for the GCSB.
The latter body was closely linked to US and British intelligence agencies through international intelligence agreements.
The law change was being rushed through to provide some after-the-fact justification for illegal government surveillance over the past 18 months.
The professors said they were not aware of any hard evidence that ''such intrusive surveillance mechanisms have played a significant role in the prevention of serious political violence or terrorist activity''.
