Joint defense privilege

The joint defense privilege, or common-interest rule, is an extension of attorney–client privilege. Under "common interest" or "joint defense" doctrine, parties with shared interest in actual or potential litigation against a common adversary may share privileged information without waiving their right to assert attorney–client privilege. Because the joint defense, "privilege sometimes may apply outside the context of actual litigation, what the parties call a 'joint defense' privilege is more aptly termed the 'common interest' rule."

Purpose

"The need to protect the free flow of information from client to attorney logically exists whenever multiple clients share a common interest about a legal matter." The common interest rule serves to protect the confidentiality of communications passing from one party to the attorney for another party where a joint defense effort or strategy has been decided upon and undertaken by the parties and their respective counsel.

Scope

The joint defense privilege does not merely protect statements made by attorney to client or attorney to attorney. The privilege also is held to cover communications made to certain agents of an attorney, including accountants hired to assist in the rendition of legal services. Furthermore, a person need not be a litigant to be a party to a joint defense agreement. The joint defense privilege also applies to "parties or potential parties sharing a common interest in the outcome of a particular claim. Only those communications made in the course of an ongoing common enterprise and intended to further the enterprise are protected.

Elements

A party seeking to assert the joint defense privilege must demonstrate that:

The communications were made in the course of a joint defense effort.

The statements were made in furtherance of that effort.