Crimes Act 1961

The master or officer in command of a ship on a voyage or the pilot in command of an aircraft on a flight is justified in using and ordering the use of force for the purpose of maintaining good order and discipline on board his or her ship or aircraft if he or she believes on reasonable grounds that the use of force is necessary, and if the force used is reasonable in the circumstances.

Every one acting in good faith is justified in using force in obedience to any order given by the master or officer or pilot in command for the purpose aforesaid, if the force used is reasonable in the circumstances.

The reasonableness of the grounds on which the use of force was believed to be necessary, and the reasonableness of the force used, are questions of fact.