“The proscribed conduct is set out in s 298K(1) of the Act:
” An employer must not, for a prohibited reason, or for reasons that include a prohibited reason, do or threaten to do any of the following:
(a) dismiss an employee;
(b) injure an employee in his or her employment;
(c) alter the position of an employee to the employee’s prejudice;
1. The predecessor of s 342(1) Item 1, was s 290K(1) of the Workplace Relations Act 1996 (Cth) (the WR Act). In Patrick Stevedores Operations No 2 Pty Ltd v Maritime Union of Australia  HCA 30;(1998) 195 CLR 1 at , the plurality said that subpara (b) “covers injury of any compensable kind” and that subpara (c) is “a broad additional category which covers not only legal injury but any adverse affection of, or deterioration in, the advantages enjoyed by the employee before the conduct in question”.
77. The authorities indicate that an employee’s position may be altered to his or her prejudice regardless of whether the employee suffers any loss or infringement of a legal right. A relevant alteration will occur if the advantages enjoyed by the employee before the conduct in question are affected adversely or are impaired in any way, subject however, to the alteration in the employee’s position being real and substantial and not merely possible or hypothetical. See generally, Community and Public Sector Union v Telstra Corporation Ltd  FCA 267, (2001) 107 FCR 93 at ; and Qantas Airways Ltd v Australian Licensed Aircraft Engineers Association  FCAFC 63 at ……….
There are circumstances in which the conduct of a formal performance management review may constitute a form of adverse action. See, for example, Construction, Forestry, Mining and Energy Union v Pilbara Iron Company (Services) Pty Ltd (No 3)  FCA 697 at . However, the circumstances disclosed by the evidence in this case differ in material respects from those in CFMEU v Pilbara Iron Company.”
Perez v Northern Territory Department of Correctional Services (2016) FCA 476 delivered 6 May 2016 per White J