Why don't teachers in California pay social security?

Question

We have a different retirement system called STRS. I was just wondering the reason behind setting up a whole new system instead of using social security thats already in place. It doesn't bother me one way or another but I was curious why teachers have a separate retirement system. Thanks!

Answer 1

because STRS was already there before SS came into being.

railroad folks have a similar plan.

Answer 2

It was negotiated that way.