From the link, the reason why they had to file BK:
“Stockton has suffered a sharp drop in revenue since the collapse of its once red-hot housing market, forcing it to cut more than $90 million in spending in recent years.
The housing boom transformed the farming city into a distant bedroom community of the San Francisco Bay area, and the bust put it at, or near, the top of national foreclosure rankings in recent years.”
……….
^^^This^^^ (not “union goons”) is the reason most municipalities are in such big trouble.