As part of her unusual defence, former Boggabri mine worker Tara Cunningham claimed that one of her drinks may have been spiked with meth by two unknown men on the weekend before the fateful drug test on Wednesday April 2 last year.

While the management team at her former employer, Downer EDI, initially took this claim seriously, it terminated her employment after receiving medical advice that it was implausible.

This was based on the test results which clocked up a meth count of 607 micrograms/litre in her samples – more than four times over the 150ug/l cut-off.

It was consequently deemed impossible to score such a high result from a single dose administered around 80 hours earlier.

FWC Commissioner Ian Cambridge agreed with this evidence in his decision last week and took aim at the Construction, Forestry, Mining and Energy Union for its support of Cunningham’s case.

“The proposition that was advanced by the CFMEU that the level of methylamphetamine detected in the applicant’s urine sample did not conclusively establish that the applicant was under the influence of a non-approved drug must be bluntly and conclusively rejected,” he said in his ruling.

“The employer [Downer] described this proposition as a technical argument, it can also be characterised as irresponsible and discreditable.

“It was highly regrettable to observe during the Hearing that an organisation which apparently conducts campaigns which strongly advocate safety in the workplace, could contemplate a proposition which, in effect, would countenance a person driving a 580 tonne truck whilst having methylamphetamine in their body at a level 4 times the reportable cut-off figure.

“Any realistic and responsible pursuit of the case on behalf of the applicant [Cunningham] should have been confined to the development of evidentiary support for the applicant’s explanation for the presence of the methylamphetamine.

“Indeed, much greater energy and focus should have been devoted to such an evidentiary position rather than any attempt to defend the indefensible.”