Any union representing government employees must be precluded from any expenditures on behalf of any political issue, political party, or politician. There is an inherent conflict of interest in which any tax payers not sitting at the table (all citizens not associated with the government union or the politicals negotiating) will necessarily get screwed. The only skin in the game either of the negotiators has is in how much money they can keep recycling between themselves...
To be sure, labor unions are about power, specifically about giving power to those who are considered generally powerless to protect themselves from both economic and work place abuses.
Under normal circumstances that union “power” is directed against those who oppose, or compete with them for scarce production resources … because all parties have something at risk, something to lose economically ... All sides have “skin in the game”.
Production Investors, Production Materials, and Production Manpower are the three economic elements in any business enterprise … with management representing ”investors”, suppliers representing “materials”, and labor representing production manpower … each challenges the other, competing for a larger share of the total revenue (a bigger piece of the pie).

What happens in the private sector:
In business, the competing forces realize that “the pie” will evaporate for all of them if any one group succeeds and gets too large or pushes too hard … that’s why there is always a push back until they are forced to come to an agreement. This did not happen in the recent “Twinky” extinction. One union amongst the many said “no, no, and hell no!” so the Twinky, along with several thousand jobs, disappeared. While this loss of jobs is a tragedy, it’s one most often avoided in the private economy sector … because all sides have “skin in the game”.

What happens in the public sector:
In government, there are no competing interests at the table. The public sector labor unions should be bargaining with those that pay them, “the people” … because that isn’t possible, they sit opposite those who are supposed to represent the people, politicians. Between the two of them there is no sense that “the pie” will disappear … on one side of the table bargainers have no “skin in the game”, no reason to push or resist, in point of fact, it is in their interest NOT to antagonize those on the other side … on the other side, the bargainers have already purchased the favor of those with “no skin in the game” (that phrase keeps popping up).
There in lies the problem … Right now, in government, the full force and power of the largest most powerful unions in the country (public employee unions) are pointed directly at the people on every level … there is little push back at the city, county, state, or federal level … no resistance because the political parties (management) have reached a symbiotic relationship with the government unions … “unions use their mandatory dues extracted from the membership to support the politically preferred projects and party, while politicians in return use their political party power to see that the government employee unions get favorable agreements so that they will not only survive, but continue to grow handsomely in wealth and power”.

Both get stronger as they support each other at the public trough.
This is done in secrecy, behind locked doors … Pols under the flag of doing the “peoples” good work, government unions cloaked under the mantle of the “working class” … neither of which is true … and we “the people”, the ones who pay the pensions and the bills, are not even at the table.