I have a juvenile on probation who is detained for violations and new offenses. As a term and condition of probation, we have access to his Facebook account. There is information in his account we would like to preserve. Does anyone see a problem with his probation officer changing his password?

Go to www.facebook.com/records and send them a preservation request. Then get a search warrant for the information that you want.

Alternatively, since you have access now you can download a copy of the persons profile: https://www.facebook.com/help/131112897028467