Record of disciplinary council from previous ward

How can I find, for the bishop, details of a disciplinary council held in another ward for a member that is now in our ward?

Assuming you are the ward clerk, you should go to LCR and select the Confidential menu item and then the option to request documents or minutes (I don't have access to those items anymore so I'm not sure of the exact wording). Once you make the request the information will be mailed to your Stake President who will then pass it on to the bishop (at least that's the way it worked a few years ago when I last did it).