The managerial prerogative is not based on legislation, but is based on case law and is present i all employment relationships. The Supreme Court has defined the managerial prerogative as the employer's ability to "organize, lead, control and assign work", cf. the case Rt. 2000 p. 1602 ("Nøkk"). What decisions that each employer may make pursuant to the managerial prerogative, is affected by potential restrictions in legislation, collective bargaining agreement, the individual employment agreement and circumstances in the individual employment relationships.
In the Bristol/Plaza case, there were no collective bargaining agreements or other regulation of gratuity in the employees' employment agreements or other applicable agreements/policies. Despite there being no regulation on the matter in agreements or otherwise , the legal starting point is that the managerial prerogative does not give the employers a unilateral right to make negative changes to the financial benefits and payments to the employees. As gratuity is a financial right, the Appeal Court found that the employees were entitled to these payments without any deductions made by the employers. This is also based on the Supreme Court case Rt. 2008 p. 856 ("Theatercafeen"), where the Court tried whether the employer could make changes to what staff members who received gratuity given by the guests. The Supreme Court found that the employer had prerogative to unilaterally decide that the gratuity were to be shared between a wider portion of the restaurant staff, and not only the waiters.
The Theatercafeen case was decided based on the facts of the specific case, but may be used as a general argument that changes to the distribution of gratuity between the employees lies within the scope of the managerial prerogative. The case does not, on the other hand, provide any answers regarding whether the employees are entitled to keep the entirety of the gratuity without the employer being able to make deductions. This was also emphasized in the Appeal Court's decision in the Bristol/Plaza case.