The bus company NZ Bus has been told to pay thousands of dollars for the way it dealt with drivers when setting new rosters.
The Employment Relations Authority has ruled NZ Bus breached its obligations of good faith when it introduced new rosters.
It has been ordered to give sufficient time for consultation to union members and has 28 days to pay $10,000 to the authority.
First Union said the rosters allowed for drivers to work up to 11 hours a day with only a 10 hour break between shifts.
The authority said NZ Bus failed to undertake a thorough consultation, and initially imposed a very short timeframe.
It said this meant drivers were denied the right to be adequately consulted.
NZ Bus argued that the roster changes were not significant, but the authority has not accepted this.