Ngai Tuhoe leader Tamati Kruger suspects those who don't conform to society's norms will be monitored by the government's spy agency.
Legislation passed this week allows the Government Communications Security Bureau to carry out surveillance on New Zealand citizens.
Mr Kruger said the new law represented a loss to New Zealand society, with one of the most dangerous aspects being that people who were different and did not conform would be targeted by the bureau.
It would be a loss to society if people were afraid to stand up and debate issues, he said.
Prime Minister John Key said he would never say who may or may not come under surveillance but that law-abiding people had nothing to worry about.