Amnesty International has singled out the Coastal and Marine Area Act in an annual report on human rights.
It examined New Zealand's human rights record together with that of 156 other countries.
The organisation's strongest criticism was directed at repression of dissent in the Middle East, Africa and elsewhere.
New Zealand chief executive Patrick Holmes says the Marine and Coastal Area Act repeals discriminatory principles in the Foreshore and Seabed Act, but does not go far enough.
He rejects a suggestion that denial of Maori exclusivity was a political compromise with the rights of other New Zealanders.
Amnesty is also critical of the Immigration Act, which permits detention of refugees and asylum-seekers for up to 96 hours, and allows people to be blocked from boarding an aircraft bound for New Zealand without being told why.