The case, WorkPac v Rossato, found that "casual" mine worker Robert Rossato was eligible to be paid "annual leave, paid personal/carer's leave paid compassionate leave and payment for public holidays" and that WorkPac could not seek "restitution" because of the money it had supposedly paid him in his hourly rate to compensate for those conditions.

This was because "Mr Rossato seeks payment of the NES (National Employment Standards) entitlements, not payments in lieu," the court said in a summary of the case.

The national president of the Construction, Forestry, Mining and Energy Union, Tony Maher, described it as a "fantastic decision that puts an end to the 'permanent casual' rort that has become a scourge in the coal mining industry and across the workforce".

"It's a decision that passes the pub test on what it means to be a casual and is consistent with community expectations that casual work is irregular and intermittent," Mr Maher said.

"Employers must now stop with the nonsense that calling a worker a casual makes them so."

The chief executive of the Australian Industry Group, Innes Willox, said the decision would allow "double dipping" by casuals and he urged the federal government to intervene with "urgent legislative reform".

The case had been viewed as a major test case on casual employment and Mr Willox said that if the judgement stood, the cost to employers on annual leave alone could be between $5.6 billion and $8 billion given that 1.6 million of Australia's 2.6 million casual employees worked on a "regular, ongoing basis".

"Casuals make up around 20 per cent of the Australian workforce, providing vital flexibility to employers and employees," Mr Willox said.

"The Fair Work Act needs to be urgently amended to define a casual employee in a simple and clear manner to address the uncertainty caused by the Federal Court's Workpac v Skene decision, and now the Workpac v Rossato decision.

"The current laws, as interpreted in these decisions, operate as a major deterrent to the employment of casuals."

In the judgement summary, the court said Workpac V Skene had a "number of unusual features" - one being that it was lodged by WorkPac less than three months after the Federal Court had delivered its verdict in an earlier high-profile case, WorkPac v Skene, which had also gone against WorkPac.

Both Mr Rossato and Paul Skene were so-called "permanent casuals", working in the situation where an estimated 40 per cent of the NSW and Queensland coal mining workforces are regarded as casuals despite having set repeating rosters set in advance for a year.

In this case, the court said Mr Rossato was employed in similar but not identical conditions to Mr Skene, and that WorkPac said Mr Rossato was a casual employee because there was no "firm advance commitment as to the duration of the employee's employment or the days/ hours the employee will work".

"All members of the court have found that, even taking WorkPac's case at its highest, Mr Rossato was not a casual employee for the purposes of the Fair Work Act and for the purposes of the 2012 [WorkPac] enterprise agreement,'' the judges said in their case summary.

"The court has found that the parties had agreed on employment of indefinite duration which was stable, regular and predictable such that the postulated firm advance commitment was evident in each of his six contracts.

"All members of the court have found that WorkPac is not entitled to restitution of the casual loading which it claimed was included in the hourly rate it had paid to Mr Rossato.

"The members of the court have found that there was no relevant mistake, and no failure of consideration such as would support restitutionary relief."

The decision's main findings were summarised as:

"One: In his employment under each of the contracts, Mr Rossato was other than a casual employee for the purposes of the Fair Work Act and not a casual FTM (field team member) under the 2012 EA:

"Two: Mr Rossato is entitled to the entitlements that he claimed under the Fair Work Act and the 2012 EA with respect to paid annual leave, paid personal/carer's leave paid compassionate leave and payment for public holidays; and

"Three: WorkPac is not entitled to either restitution or to 'set off' against its liabilities any of the payments made under the six contracts of employment."

Read full coverage of the verdict and reaction to it in Thursday's Newcastle Herald.

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