The fiduciary exception to attorney-client privilege is fertile ground for trust litigation. I’ve seen many situations where the attorney is advising his or her client on the same matter, with the client as the Trustee and as the beneficiary of a trust. Not only are there conflict of interest issues for the client, but the client many times inadvertently loses privilege when not clarified by the attorney at the time.
Application of the fiduciary exception varies by state and jurisdiction, with the rule restricted or eliminated in the four largest states. Here is a new article reviewing the current status of the fiduciary exception:
Idaho Trustee 