20. (1) An employer shall not penalise or threaten penalisation of a worker for—

(a) invoking any right conferred on him or her by this Chapter,

(b) making a complaint to the Workplace Relations Commission that a provision of this Chapter has been contravened, or

(c) giving notice of his or her intention to do either of the matters referred to in paragraph (a) or (b).

(2) Subsection (1) does not apply to the making of a complaint that is a protected disclosure within the meaning of the Protected Disclosures Act 2014.

(3) In proceedings under Part 4 of the Act of 2015 in relation to a complaint that subsection (1) has been contravened, it shall be presumed, until the contrary is proved, that the worker concerned has acted reasonably and in good faith in forming the opinion and making the communication concerned.

(4) If a penalisation of a worker, in contravention of subsection (1), constitutes a dismissal of the worker within the meaning of the Unfair Dismissals Acts 1977 to 2015, relief may not be granted to the worker in respect of that penalisation both under section 23 and under those Acts.

(5) In this section “penalisation” means any act or omission by an employer or a person acting on behalf of an employer that affects a worker to his or her detriment with respect to any term or condition of his or her employment, and, without prejudice to the generality of the foregoing, includes—

(a) suspension, lay-off or dismissal (including a dismissal within the meaning of the Unfair Dismissals Acts 1977 to 2015), or the threat of suspension, lay-off or dismissal,

(b) demotion or loss of opportunity for promotion,

(c) transfer of duties, change of location of place of work, reduction in wages or change in working hours,

(d) imposition or the administering of any discipline, reprimand or other penalty (including a financial penalty), and

(e) coercion or intimidation.