ABBOTT government frontbencher Christopher Pyne has blamed the New South Wales Liberal Party for creating a "storm in a teacup" over Royal Commissioner Dyson Heydon.
On Thursday, Justice Heydon pulled out of a Liberal Party function where he was due to give a speech to the NSW Bar Association next week.
His withdrawal ahead of media reports on Thursday prompted the Federal Opposition to call for his resignation, amid claims of a perception of bias.
On Friday, however, Mr Pyne told Channel 9 the controversy was "the greatest storm in a teacup in years".
Mr Pyne joined Prime Minister Tony Abbott in defending Justice Heydon, the head of the Royal Commission into trade unions, which was pledged by Mr Abbott during the 2013 election.
He said Justice Heydon had behaved appropriately through the entire process.
Mr Pyne said why a barrister in the Liberal Party "thought it was a good idea to invite him is beyond me".
NSW Liberal Party chief Tony Nutt released a statement on Thursday saying it was hard to describe the event as a "significant fundraiser" given tickets were only to cover the costs of holding the event.
However, invitations to the event, the Sir Garfield Barwick Address, were made public as early as April and depicted a party logo and appeal for donations on top of the entry fee.
The royal commission Justice Heydon has led has been used by the government in Question Time as a key lever for political attacks against Labor leader Bill Shorten.
On Friday, Mr Shorten said the fact Justice Heydon had been billed for the event was, he believed, "a smoking gun of political bias".
The Opposition is also understood to be considering legal action over the issue.
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