Opposition parties say the Government has given in to lobbying from the oil companies with a late change to a bill introducing a harder line on anti-mining protests at sea.
Public submissions have already been heard on the The Crown Minerals (Permitting and Crown Land) Bill, but the Government has now put forward an amendment that would make it an offence to interfere with offshore mining operations.
Energy and Resources Minister Simon Bridges put forward the late change, which would make it an offence to interfere with, or damage, ships or structures used in the operations. He is proposing prison terms and fines of up to $100,000 for protesters.
The Labour Party's energy spokesperson says the law change is not about safety, but an attempt to shut down protests against deep-sea oil drilling.
Moana Mackey believes the Government was lobbied by the oil and gas industry to make the law change.
The Green Party says the Government is putting the business agenda of overseas multinationals ahead of the legal and human rights of New Zealanders.
Energy spokesperson Gareth Hughes says it is singling out the oil industry for legal protection and bowing to lobbying from companies.
Mr Hughes says the Government is pushing the amendment through without proper scrutiny and it should go back to the committee for further consideration.
But Energy Minister Simon Bridges says the Government believes it is the right thing to do, to provide certainty and allow companies to go about their lawful business.
He defended the legislation, saying the Government wants to stop criminal damage - not lawful protest.
The amendment is also opposed by a group of prominent people, including former prime minister Sir Geoffrey Palmer and New Zealander of the Year Dame Anne Salmond, who say a legal opinion shows that the proposal may breach the rights to freedom of expression and peaceful assembly.
The group says it goes against a tradition of protest at sea, including past anti-nuclear protests.
Peter Williams, QC, told Radio New Zealand's Morning Report programme on Tuesday the legislation is completely against New Zealanders and for foreign mining companies.
He described it as fascist, draconian and shocking legislation which people must be aware of and act to stop being passed.
But Petroleum Exploration and Production Association chief executive David Robinson says the changes are needed - particularly around survey vessels - to keep people working on the ships as well as protesters safe while at sea.
The bill is due for debate again in Parliament this week.
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