A Queensland mine worker has won a $37,000 unfair dismissal payout after the Fair Work Commission found he was fired based on a flawed drug test. The worker had admitted to smoking cannabis the night before, but had taken an employer-provided self-test which read negative. However, he was subject to an on-site test the next day, which had a different threshold for a positive reading.
In this article, we’ll look at the events of this unfair dismissal QLD case Maxwell Parks v WorkPac Pty Ltd [2025]. We’ll also look at a much more clear cut case of a rail worker who was justifiably fired for cannabis usage.
Employer stuffs up drug test, forced to pay dismissed worker over $37K
Maxwell Parks started working for mining recruitment firm WorkPac in May 2021 as a mobile plant operator. He was assigned to the Boundary Hill Mine, a site operated by Batchfire Resources near Biloela, Queensland. His role was safety-critical, involving the operation of massive rear dump trucks and dozers. The event that led to his termination of employment took place on the evening of 25 January 2025.
In his Fair Work unfair dismissal claim, Mr. Parks said that he smoked half a joint of prescription cannabis. He claimed it was provided to him by an acquaintance to help him cope with severe situational stress involving his children. On the morning of 26 January 2025, Mr. Parks took a proactive safety step by using a self-test kit provided by Batchfire at home. The test returned a negative result, and believing he was fit for work, he reported for his shift.
Drug test with already-opened kit led to dismissal
During that shift, he was directed to undergo a “for cause” drug test because his housemate had returned a non-negative result. Mr. Parks’ initial test was non-negative, but a subsequent retest was negative. Despite Batchfire’s policy stating that a negative retest should allow a return to work, he was sent home. The next day, Mr. Parks again performed a self-test at home which was negative. Upon arriving at the mine, his first test was recorded as negative and signed off by a supervisor.
However, later that shift, he was told the result had “turned” to non-negative outside the 10-minute validity window specified by the manufacturer. A further test was conducted using an already-opened kit, which Mr. Parks argued broke the chain of custody. Laboratory results later confirmed THC levels of 15ng/ml and 17ng/ml. WorkPac issued a show-cause notice on 31 January 2025 and finalised his termination of employment on 4 February 2025.
Alleged drug tests were inconsistent, results were unfairly changed
Mr. Parks subsequently lodged a Fair Work unfair dismissal claim. He argued that his termination of employment was unjust because he had acted in “good faith” by using the self-testing kits provided by the site. He highlighted a critical technical discrepancy between the different drug tests he had. He said the Batchfire self-test kits were aligned with the AS 4760:2006 standard, which has a 25ng/ml threshold. Meanwhile, the laboratory and onsite screening used the stricter AS/NZS 4760:2019 standard of 15ng/ml.
He argued this effectively produces false non-negative results for anyone with trace levels between the two standards. Mr. Parks contended that this essentially set employees up to fail. Mr. Parks also raised serious concerns about the testing process. He alleged that on 27 January 2025, the paperwork for the drug test was changed to a non-negative result without his knowledge after it had been signed as negative. He submitted that his unblemished record and transparency about his “self-medicating reasons” should have been considered.
Employer said zero-tolerance policy justified termination of employment
In response to Mr. Parks’ Fair Work unfair dismissal claim, WorkPac argued that his termination of employment was justified due to breaching their zero-tolerance drug policy. It contended that their policy, which prohibited any concentration above 0%, took precedence over the host employer’s more lenient procedures. WorkPac stated that operating 200-tonne machinery with any drugs in the system was an unacceptable risk. WorkPac argued that the positive laboratory results provided an incontrovertible valid reason for termination of employment.
Drug test was flawed, huge unfair dismissal payout awarded
Mr. Parks’ Fair Work unfair dismissal claim was heard by the Fair Work Commission in August 2025. It found that the investigation conducted by WorkPac did not factor in all the circumstances.” Specifically, it failed to address the procedural flaws raised by Mr. Parks. The Commission found that Mr. Parks was a “model employee” who had been proactive and honest. It noted several deficiencies in how the testing was undertaken, including the breach of the chain of custody and testing outside the valid manufacturer’s window.
The Fair Work Commission accepted the evidence that Mr. Parks believed he was in compliance with site rules. It said it had “no doubt” that had the self-tests provided to him by Batchfire returned a non-negative result, he would not have turned up for work. It was also noted that the amounts of THC were “negligible” and not detectable by several initial tests.
Ultimately, the Commission ruled that the termination of employment was unfair. Reinstatement was denied as the relationship was “irrevocably broken,” but compensation was awarded. The Commission calculated six months of lost wages but applied a 50% reduction for contributory misconduct, as Mr. Parks did have THC in his system. WorkPac was ordered to pay him $37,222.50.
Rail worker dismissed for testing three times over legal cannabis limit
Another unfair dismissal QLD case that involved termination of employment for cannabis is Zachary Wight v Queensland Rail Limited [2025]. Zachary Wight started working for Queensland Rail in 2018 as a shunter. The role of a shunter is classified as safety-critical, involving the manual attachment and detachment of rail vehicles. Mr. Wight mainly performed these duties in the “danger zone,” an area characterised by moving trains and overhead electrified infrastructure. Shunters must direct trains, operate points and signalling equipment, and conduct safety checks.
Prior to the events that led to Mr. Wight’s sacking, for about two years he had been largely away from work on unpaid leave for mental health reasons. During this period, Queensland Rail implemented a “health plan.” In his Fair Work unfair dismissal claim, Mr. Wight claimed that this plan required him to provide monthly counselling reports undertaken at his own expense.
Tested positive on first day back at work
On 15 August 2024, his first day returning to work, he was required to undergo a routine alcohol and drug test. The results of this screening indicated a positive presence of THC-Cannabis at a level of 17ng/ml. This figure was more than triple the Australian Standard cut-off of 5ng/ml. Following the positive test, Queensland Rail initiated disciplinary proceedings. Mr. Wight admitted to consuming cannabis in the days preceding his return to work but maintained he had stopped by 13 August 2024. He stated he had not consumed the substance on 14 August or 15 August.
Rather, he said he consumed it on an earlier day when he was stood down from duty without pay. At the time, he believed that he was not considered able to be called up for duty. Despite his explanation, Queensland Rail moved to terminate his employment on 14 November 2024. The letter of termination emphasised the organisation’s zero-tolerance drug and alcohol policy. Mr. Wight subsequently lodged a Fair Work unfair dismissal claim.
Argued he was self-medicating due to employer’s conduct
In his Fair Work unfair dismissal claim, Mr. Wight argued that his conduct was a direct result of a hostile work environment and poor management by Queensland Rail. He claimed that for more than two years prior to his sacking, he had been “unjustly targeted.” Mr. Wight claimed that he was made a “scapegoat” for safety incidents around the yard. On top of that, alleged that Queensland Rail’s conduct was responsible for the breakdown of the relationship with his partner.
Mr. Wight’s central argument was that he was “self-medicating” with THC-Cannabis to manage a psychiatric injury he believed was caused by his employer’s treatment. He submitted that his Fair Work unfair dismissal claim could not be decided without considering the actions of Queensland Rail in the over three years prior to his sacking. Mr. Wight further alleged that the organisation had “unlawful and unreasonably” stood him down on unpaid leave without written notice nor consultation. He claimed that this breached the Rail Safety National Law QLD and Queensland Rail’s enterprise agreement.
Employer thought it had a slam dunk case against worker
In response to Mr. Wight’s Fair Work unfair dismissal claim, Queensland Rail argued that it had no reasonable prospects of success and should be thrown out. The employer maintained that the safety-critical nature of the shunter role made the breach non-negotiable. Queensland Rail said that Mr. Wight’s decision to return to work with a high level of THC in his system was the “complete opposite” of the behaviour expected of a rail operator. The organisation’s chief medical officer provided evidence that posting a positive result at 17ng/ml two to three days after a single usage would be “extremely unlikely.”
The organisation further noted that Mr. Wight’s submitted evidence was incoherent, “extremely difficult” to understand and largely unrelated to the basis of his termination. The Fair Work Commission twice denied the Queensland Rail’s applications to reject Mr. Wight’s claim without proceeding to a full hearing. It noted that its power to reject a claim should be used “sparingly” and approached with “caution.” The Commission opted to accept all of the documents Mr. Wight filed. It also allowed him to provide oral evidence, acknowledging that he “struggled” to prepare his written case.
Fair Work: Worker’s ‘reckless’ behaviour got him fired
Mr. Wight’s Fair Work unfair dismissal claim was heard by the Fair Work Commission in February 2025. It ruled that the high-range level of THC-Cannabis was a valid reason for the termination of employment. The Commission did not accept Mr. Wight’s argument that his mental health issues and workplace history served as mitigation. It found that the history of circumstances between Mr. Wight and Queensland Rail were not the cause of his termination of employment.
The Commission noted that a separate review by the Queensland Industrial Relations Commission had confirmed Mr. Wight suffered a psychiatric injury. However, the review had also determined that the injury arose from management action that was “reasonable” and conducted in a reasonable way. The Commission concluded that Mr. Wight was willing to “recklessly try and estimate” whether his drug test would pick up cannabis in his system. It said that Mr. Wight did not have the right to self-medicate in a covert manner, particularly given the nature of his work. As the conduct undermined the safety requirements of a dangerous working environment, the Fair Work unfair dismissal claim was rejected.
Read more: ‘I just shat myself’: Dismissed Worker Tries to Evade Drug Test
Have you been dismissed for a positive drug test?
If you’ve been sacked after a workplace drug test, that doesn’t automatically mean the termination was lawful or fair. As this case shows, flawed testing procedures, inconsistent standards, or failures in process can turn a seemingly clear-cut termination into a successful unfair dismissal claim.
We at A Whole New Approach (AWNA) regularly assist workers terminated following drug and alcohol testing. We also help with general protections, forced resignation, discrimination and sexual harassment claims. Strict time limits apply — you generally have just 21 days from the date of termination to lodge a Fair Work claim. So call us now 1300 766 700 for free, confidential advice.
