A LEADING constitutional law expert says any new laws seeking to silence green groups are likely to be challenged in the High Court.
As a parliamentary inquiry into the Register of Environmental Organisations prepares for a series of hearings, Coalition MPs and the mining industry have called for listed groups to lose their charity and tax-deductible donation status.
Several submissions have also claimed political advocacy is not within the bounds of environmental groups' roles, despite a 2010 High Court precedent enshrining political advocacy as a key part of environmental protection efforts.
University of New South Wales constitutional law expert Professor George Williams said on Friday that the Constitution protected such political communications from "infringement by state and federal laws".
He said any federal law that "prevented charities or other bodies from engaging in such communication could well fall foul of the guarantee, and could be challenged in the High Court".
Prof Williams said the 2010 High Court case had already shown a future challenge was "a real possibility" if the government tried to legislate a ban on political expression.
Lending support to Prof Williams' view, the Fund-raising Institute of Australia, Philanthropy Australia, Civil Liberties Australia and the Myer Foundation all defended environmental groups' political advocacy.
Myer Foundation chief executive Leonard Vary said the law upheld "the right of charities to undertake advocacy" and any reduction to the scope of activities environmental organisations could undertake would "reduce their ability to protect the environment".
The foundation has donated more than $13 million to environmental causes.
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