Does anyone know of a way to reverse the hierarchy on a string of joints?

example:
set up a series of 9 joints in a straight line that starts on the left side of the screen. The left most joint will be the root joint. Let's call it "joint 1" If you rotate joint 1, all the rest of the joints will move and stay in relation to joint 1's rotation. If you rotate joint 5, then joints 6,7,8,and 9 will move and stay in relation to joint 5's rotation.

Now, if you could reverse the hierarchy then when you rotated joint 5, joints 4,3,2,and 1 would move instead of 6,7,8, and 9.

If there is a way to do this, I need it to be keyframeable so I can make the switch during animation. Any ideas would be helpful