Mr Boscawen and new Act MP Hilary Calvert, of Dunedin, are on a mission to help raise public awareness about the effects of the changes to the foreshore and seabed legislation - the Marine and Coastal Area (Takutai Moana) Bill.
"National has overreacted. Our aim is to raise awareness and apply political pressure on National to abandon its plans for the Bill. It is wrong and racist," Mr Boscawen said in an interview.
The campaign has shades of the National Party's "Iwi-Kiwi" campaign of 2005 but Mr Boscawen said Act was trying to protect the economic benefits of all New Zealanders rather than any particular group.
The new legislation would advantage some people more than others and within Maoridom, some iwi would be substantially better off than others if, as expected, the Bill passed next year.
New Zealanders were not generally aware of the breadth of the proposed changes, he said.
"They think it is a big, boring yawn.
We think National is relying on people not becoming aware of it before it is passed."
Of concern to Mr Boscawen was the ability of an attorney-general to agree to "back-door deals" with iwi on claims for customary title.
Those negotiations could take place behind closed doors.
Any attorney-general could give iwi economic control of the foreshore and seabed at the expense of other New Zealanders, including resources not nationalised for the economic benefit of the country.
The Crown Mineral Acts protected gold, silver, uranium and petroleum rights on the seabed.
However, iron-sands off the coast of Taranaki and Waikato were not protected.
Although they were now owned by the Crown, title could pass to local iwi.
Although oil and petroleum rights would continue to be owned by the Crown, Mr Boscawen saw possibilities of iwi charging companies to bring in oil drilling rigs or lay pipes to pump the oil on to the shore.
"If the Bill is passed, it is irreversible.
It will transfer economic control and power for generations to come."
Ms Calvert was concerned general use of some beaches by tourism operators would be affected by iwi gaining customary title to places such as the Karitane foreshore and seabed.
Commercial horse-trekking across the beach, kayak tour operators or general tourism operators could be asked for financial concessions by the local iwi.
Mr Boscawen said the 2004 legislation was dealt with by Parliament's business select committee and he was critical that this time, the Maori affairs committee would be hearing the submissions.
All committee members are of Maori descent.
National had Tau Henare (chairman), Simon Bridges and Paul Quinn, Labour had Kelvin Davis, Parekura Horomia and Mita Ririnui and the Maori Party had Hone Harawira (deputy chairman)After representation, Mr Boscawen and Green MP Metiria Turei, from the business select committee, were included on the panel to hear the submissions but they had no voting rights.
The Bill should have been considered by a wider group of parliamentarians.
Mr Boscawen and Ms Calvert will spend the next three months speaking at public meetings about the Bill.
Last night they were in Dunedin.
