Tight budgets and heavy workloads are being blamed the "record levels" of personal grievances being laid by police employees.
The New Zealand Police Association confirmed there had been 25 cases since June 2013.
Among those complaints are two from staff members at Auckland central police station's file management centre.
The pair allege they were bullied between 2008 and 2014 and faced severe emotional harm as a result.
They also said when they took their concerns to managers, they were not taken seriously and called in an employment lawyer who filed an official complaint.
Greg O'Connor, the association's president, said that employment practice managers who were experts in the field of human resources were axed from police two years ago after a restructure.
Employment practice managers were hired after the 2007 Police Commission of Inquiry into police conduct.
The work load is now being picked up by staff members who have little experience in the field.
"Police are heavily stretched at every level and this is where shortcuts get taken. There are less people to deal with the issues and more issues arising. Often when you try to save money in one area, you end up spending it in another anyway," said O'Connor.
"Everyone talks about clearing out the back room, but when you clear out the back room you create more problems because you clear out the wrong people."
He added that apart from the cost of paying employees out for personal grievances, police also have to foot the bill for the cost of mediations and lawyers.
O'Connor said that police also modified the Code of Conduct process which removed the option of an external party hearing disciplinary matters.
"Somehow there's a bit of a myth that police are easy on their own, the opposite couldn't be more true," said O'Connor.
"Externals tended to be people who took a broader view of the issues, whereas police are very hard on their own, much harder."
The association is often heavily involved in disciplinary proceedings, but O'Connor would not comment about individual cases.