What is Adverse Action by an Employer — and What Must an Employee Prove?

“Adverse action” has a specific meaning under the Fair Work Act 2009 (Cth). It is not enough that an employer’s decision was harsh, unreasonable or poorly handled. The action must have been taken for a prohibited reason.

​

An employer takes adverse action against an employee by dismissing them, injuring them in their employment, altering their position to their prejudice, or discriminating between them and other employees. In practice, this may include demotion, reduced hours, lost opportunities, disadvantageous changes to duties, disciplinary action or threats of such action.

​

A threat can qualify even if it is not carried out, and prospective employees and independent contractors may also be protected.

​

The employee must identify the protected reason alleged to have been a substantial and operative reason for the adverse action. It need not have been the sole, dominant or predominant reason. Once the allegation is properly raised, the employer bears the reverse onus of proving that the prohibited reason was not among its substantial and operative reasons.

​

Common examples include:

• exercising a workplace right, such as making a complaint or enquiry about employment, requesting an entitlement or participating in a lawful process;

• possessing a protected attribute, including disability, age, race, sex, pregnancy or family and carer’s responsibilities;

• engaging, or declining to engage, in lawful industrial activity; or

• being temporarily absent because of illness or injury in protected circumstances.

​​

To establish a claim, the employee must prove the relevant facts: that the workplace right or protected attribute existed, that the adverse action occurred, and that the allegation of a prohibited reason is properly raised. Timing can be powerful evidence—for example, a dismissal shortly after a complaint—but timing alone is not always decisive.

​

Once the prohibited reason is alleged, section 361 creates a reverse onus: the employer is presumed to have acted for that reason unless it proves otherwise. The employer will usually need evidence from the actual decision-maker explaining the reasons for the decision. Contemporaneous documents, consistent explanations and a fair process can be critical. A lawful reason does not cure the decision if a prohibited reason was also a substantial and operative reason.

General protections claims differ from unfair dismissal claims. The question is why the action was taken, not simply whether it was fair. Remedies can include compensation, penalties, injunctions and reinstatement. Where dismissal is involved, an application to the Fair Work Commission generally must be lodged within 21 days after the dismissal takes effect.

​

The practical lesson for both sides is to preserve the complaint, decision and communication trail early. In adverse action litigation, the documents—and the reasons of the real decision-maker—often decide the case.

​

Sources: Fair Work Commission — General protections and adverse action; [Qantas Airways Ltd v Transport Workers Union of Australia [2023] HCA 27](https://www.hcourt.gov.au/sites/default/files/eresources/2023/HCA/27.pdf); Fair Work Act 2009

​

Disclaimer: This article provides general information only and is not legal advice. It does not create a solicitor-client relationship.