When you give money to an environmental group like Greenpeace or the WWF, should you be able to claim it back as a tax-deductible donation?
The oil and gas industry says some environmental groups are abusing the system by using donations to subsidise illegal activism instead of doing "practical work to conserve and protect the environment".
The inquiry has seen industry groups clash with environmental groups. The NSW Minerals Council, representing the state's $21.1 billion mining industry went after the Lock the Gate Alliance in its submission.
Queensland MP George Christensen has taken the accusations even further, branding environmental groups as "eco-traitors" and comparing their behaviour to a character from Lord of the Rings.
"What these eco-traitors really want to do is to shut down the coal industry completely and they do not care if it takes a World Heritage Committee label of 'in danger' to do it," Christensen said in March, speaking about the activist groups fighting to save the Great Barrier Reef
"They have got what they wanted, and yet they act like Wormtongue from Lord of the Rings, flying overseas and whispering in the ears of the decision-makers and diplomats who have anything to do with Unesco and the World Heritage committee, poisoning their minds on the state of the reef," he said.
During the inquiry's hearing in Queensland on Tuesday, Christensen fired off a tweet that outraged environmental groups.
A prominent judge has disputed claims by Liberal MPs such as Christensen and Hawke, who say the work of environmental groups should be limited to nature conservation activities.
Environmental groups say they are under attack from a government in the pocket of mining companies. They feel as though the fossil fuel industry gains far more money in tax subsidies than green groups.
It's an issue that has seen industry groups go to war with environmental groups, but how much money are we really talking here?
Many of the groups who made submissions to the inquiry are small volunteer not-for-profits, who say they rely on tax deductible status to secure large donations from the general public.
Alexandra Lee is a politics reporter for BuzzFeed News and is based in Sydney, Australia.
Contact Alex Lee at firstname.lastname@example.org.
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