Earlier quoted context omitted.
We see that all the time. You can read articles in major newspapers about the "rubber rooms" where teachers who can't be fired -- but who certainly also can't be put in front of a class -- are required to spend their workdays.
Why can’t they be fired? AFAIK, tenure generally does not protect teachers who do grossly illegal acts, such as assaulting a student.
Do you have to leave them in front of kids teaching students until they're convicted?
What if that takes months? Or never actually happens? But the teacher has crossed the line inappropriately enough times that no parent wants their kid in the same room with him?
In the most positive light, a union might protect a genuinely good teacher being unfairly accused or targeted for political reasons from being put out of work. But sometimes following the processes for ensuring that can be so unreasonable to work through on a practical level that it's easier to just keep them employed but away from students until it gets resolved or they quit.
There's a famous PDF that gets shared when this comes up (although it's geared toward an incompetent teacher):
https://reason.com/wp-content/uploads/assets/db/126393089187...