Not just police, but teachers unions are also well known for protecting bad teachers.
Some time in the past I had a mildly critical system in a remote office go down. A technician would have to simply replace a part. However, because it required a Union guy to go in there to remove a screw first, it had to wait over the weekend --meaning the company now had to take modest losses over the weekend.
The guy couldn't sneak in a screw driver as that could potentially end up costing the company more money.
This is where unions earn some of their great reputation among stiffs.
Or the company didn't want to pay OT for it?
I'll leave it to the reader to decide which is more likely.
Talk about waste of resources, fuel, etc., etc.
Oh, Oh, Oh! I know, if they let this one time slip HERE in THIS INSTANCE is where the SLIPPERY SLOPE applies, but, obviously no where else, especially in politics.
That attitude pervades the public sector an infuriates the people they are supposedly serving.
Also, the library is open during school hours, so does the teacher not teach during that time? The school has replaced the lost librarian but is effectively short a teacher now.
And who makes the hiring and firing decisions at this library anyway? The union is to blame for management not hiring a replacement?
I put in the request and about 3 weeks later, two people came to move the desk. I'd already unplugged any wiring, so one guy simply picked it up and rotated it. At that point, I found out my network cable (this is in the days before WiFi) for my PC was too short to reach the new desk location. I had to put in another request for wiring, and had to wait a week and a half for someone to come with a longer cable. During that time, I sat on the floor, with my monitor sitting on my chair. While installing the new cable, he asked if I'd unplugged the previous cable before the desk move. When I told him yes, he told me not to worry and that he wouldn't note that, but that I shouldn't do it again.
While I totally understand work rules that exist to ensure that workers aren't being made to perform duties that they're not contracted for AND to prevent companies from simply doing end-runs around them, when things reach this level of absurdity, it really sours things. Of course, the nature of "contract" is that common sense is hard to dictate and it does open the slippery slope. "I was just moving the desk in my cube" becomes "I was just moving the desk to the cube next door" to "I was just moving it on the same floor" etc.
Both categories of unions have problems and benefits, but they don't overlap 100%.
Private sector unions really depend on the industry and the union itself. they can be good, they can be bad. the only time inreally have a problem with them is when they arent voluntary.