The case, which began on Tuesday, is an attempt by the AWU to end widespread worker exploitation and wage theft in the fruit and vegetable picking industry through the abuse of piece-rate payments.
The FWC has now heard from an array of witnesses who have highlighted the need for a minimum-wage safety net to end the current piece-rates system, which is open to abuse and has often seen workers do backbreaking work only to be paid as low as a few dollars an hour.
On Thursday the AWU's expert witness, Dr Elsa Underhill from Deakin University, gave detailed evidence of widespread systemic wage theft and worker exploitation in the industry.
Dr Underhill's extensive academic research into piece-worker earnings clearly showed that on average piece-workers earn well below the minimum award rates.
Under cross-examination, a barrister from the Australian Fresh Produce Alliance tried to criticise Dr Underhill's research as being targeted at overseas workers and hence not representative of the entire workforce.
But that only reinforced the AWU's case, as overseas workers make up at least around 60% of the horticulture workforce and, due to their often poor language skills and added pressure to work on regardless, or jeopardisetheir temporary visas, are often at the most at risk of piece-rate abuse.
Later that day claims presented to the commission, and in the wider community, by the National Farmers Federation, that the AWU wants a total end to piece rates, were also debunked.
AWU cross-examination of NFF witnesses revealed that the farmers' group had provided inaccurate and inflammatory information to farmers when asking them to complete an online survey about piece work.
For example, the material sent in conjunction with the survey indicated the AWU is attempting to "effectively abolish" piece rates from the Horticulture Award, when the union is actually only trying to introduce a safety net.
Other evidence from farmers presented to the commission also confirmed it is common for workers to earn well below award rates, even at the better farms which have presumably been used by the NFF for their evidence.
The farmers' evidence also showed workers played little or no role in setting the piece rates, with these instead determined by the farmers and communicated to the workers.
On some occasions, farmers even retrospectively changed the piece rates at the end of the shift, based on what had been picked.
Earlier in the week the FWC heard detailed first-hand evidence from some of those directly affected by the flawed system, and from those trying to help them.
Three workers from a non-English speaking background - Mr Wang, Ms Hsu and Ms Ee - gave detailed evidence about being paid well below award rates for picking work and the poor conditions they were forced to work under.
Seven AWU organisers told the commission of piece workers receiving well below award rates, not receiving any income at all while being directed to perform farm maintenance work or picking damaged fruit, and the problems with trying to enforce the current award, given the vague and subjective payment conditions for piece workers.
And Dr Joanna Howe explained her extensive research into the industry, which has identified widespread compliance issues.
The hearing is continuing in the Fair Work Commission.
