Limit the turn rate on a character?

Hi, I’d like to limit the rate at which a character can turn left or right. I thought about simply capping the input-value in my “Axis-functions”, but since it’s a network game, this would probably be a potential exploit, allowing the client to override the limitation.

I want the camera (3rd person) to rotate immediately and with no limit, but the character should follow that rotation at a limited rate. My guess is that there is some kind of value to set somewhere, but I don’t know where. Or do I have to code this myself?..