The Green Party says the Terrorism Suppression Act should be scrapped or at least reviewed in the light of the latest development in the Urewera raids case.
The Crown on Wednesday issued a stay of proceedings, which means four people who had been charged with being part of an organised group will not face retrial.
In March this year, Tame Iti, Te Rangikaiwhiria Kemara, Urs Signer and Emily Bailey were convicted of the illegal possession of firearms and restricted weapons in Te Urewera National Park in 2007 and will be sentenced on 24 May.
However, the jury could not reach a verdict on the main charge of being part of an organised criminal group.
The raids, in which 17 people were arrested, were the first under the Terrorism Suppression Act.
Last year, charges against 14 other people were dropped after the Supreme Court ruled that the evidence was collected illegally.
Greens co-leader Metiria Turei says the law was botched from the start and should never have been passed. She says subsequent laws regarding police surveillance have arisen out of the act and also need to be scrapped.
Prime Minister John Key concedes the Terrorism Suppression Act it is not working well and says it should be improved.