There is little case law relating to the question of reasonable additional hours and it appears nothing relates to professional employees. The reasonableness or otherwise of additional hours was considered by the (then) Federal Magistrates Court and, on appeal, the Federal Court. The matter related to a worker employed as a fish keeper who was dismissed after four months when he refused to work additional hours performing maintenance, including working weekends and public holidays.
The worker tried to negotiate time off in lieu rather than overtime payments because he had an outside business interest, but the employer refused and dismissed him. The magistrate’s decision demonstrated that an employee’s ‘personal circumstances’ (which are relevant to determining whether overtime is ‘unreasonable’) are to be understood in the broad sense and are not limited to family commitments or caring responsibilities. It was determined that the request to work additional hours was unreasonable in the circumstances.
However, the primary reason why the court considered that the employer had failed to establish that the imposition of further overtime on an involuntary basis was not unreasonable was because it failed to provide evidence about how much overtime the employee worked from time to time, either specifically or on an average.
The employer needed to produce this evidence to demonstrate that, given the total amount of overtime worked by the employee, the imposition of additional involuntary overtime was not unreasonable. Whether the imposition of a requirement to work three hours on a weekend, Saturday or a Sunday, or a public holiday, was reasonable would depend on the amount of overtime an employee ordinarily works. See Brown & Premier Pet  FMCA 1089 (6 November 2012); Premier Pet Pty Ltd trading as Bay Fish v Brown (No 2)  FCA 167 (5 March 2013).