A PROMINENT Australian legal expert says he believes the Gillard government’s carbon tax is unconstitutional and that the three largest states stand a chance of successfully overturning the legislation in the event of a High Court challenge.

The University of New England academic and practicing barrister, Bryan Pape, has provided legal advice to conservative policy think tank, the Institute of Public Affairs, that says the carbon tax legislation — due to come into effect on July 1 — could be challenged on several grounds including that, ”the Commonwealth cannot tax State property: Legally carbon dioxide emissions are State property”.

The advice goes on to say that, in Mr Pape’s legal opinion, ”the Commonwealth cannot impose a carbon tax and other related penalties within the same Act. The Commonwealth cannot introduce a carbon tax within its external affairs powers”

Mr Pape — a specialist in taxation and administrative law — made headlines in 2009 when he mounted a High Court challenge over Labor’s $42 billion stimulus package, arguing that the $900 payments to individuals exceeded the federal government’s taxation powers.

“These greenhouse gases are property owned by the States and it is impermissible for the Commonwealth to impose any tax on any property of any kind belonging to a State,” Mr Pape said.

The full bench of the court ruled in favour of the Commonwealth by a margin of 4-3.

IPA Climate Change policy director, Tim Wilson, told the National Times today that the think tank had commissioned the advice in a bid to prod the states into action against the carbon tax, a piece of legislation the conservative body has long opposed.

”The IPA commissioned a legal opinion because state governments have sat on their hands and let the Gillard government introduce a tax that they could potentially stop,” he said.

”Only the High Court can decide the constitutionality of the carbon tax, but there are clear grounds to challenge it according to one of Australia’s top administrative law minds.”

Mr Wilson said the full text of the legal opinion would not be released ”pending a possible legal challenge.”

”A copy has being provided to the Premiers and Attorneys-General of the states with the best legal standing for a potential challenge – New South Wales, Queensland and Western Australia,” he said.

The legal advice will arrive on the desks of state premiers as they prepare to travel to Canberra this week for Friday’s Council of Australian Governments meeting, where, for the first time in 4½ years in office, Labor will be outnumbered at the negotiating table.

NSW, Victoria, Western Australia and Queensland are all under conservative rule and a new opinion poll has today revealed that federal Labor now trails the Coalition in every state and territory on both primary votes and on a two-party preferred basis.

The Newspoll survey, taken between January and March, shows the government is down from between three and six percentage points on primary vote and two to five points after a distribution of preferences.

The analysis of the quarterly figures reveal that the government’s electoral standing has sunk well below its 2010 election result, with support in every voting group and every state lagging behind its levels of support that resulted in a minority Labor rule.

The poll shows that if an election were held today, the carnage would be most concentrated in Queensland, where all but one or two of the state’s eight federal Labor MPs are likely to be wiped out.

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