Joint Defense Agreement Privilege
Since the existence of common interests is not as obvious as in the context of the process, it is particularly important that clients and lawyers document the beginning, duration, scope, limits and end of an agreement of common interest. Creation is important to enable the parties to determine precisely when the common interest began in the event of a subsequent dispute. To maintain the privilege of communicating with others, a party must generally demonstrate three things: that the communication was made in accordance with a common defense, that the communication was made to further the objectives of that common defense, and that the privilege was not otherwise removed (i.e., the common defenders do not share the communication beyond their core group). The conditions, scope and limits of the common defence or public interest privilege may vary considerably from one jurisdiction to another. State and federal courts differ as to whether they recognize a common defence or public interest privilege and to what extent such a privilege applies. The need for a separate lawyer for different defendants in the same dispute illustrates one of the risks of a common defence. The interests between parties with different lawyers are rarely completely identical. If these divergent interests evolve towards real differences in approach, strategy or solution, the predicate of common defence is called into question. „The need to protect the free flow of information from one client to another makes sense whenever multiple clients have a common interest in a court case.“  The Common Interest Rule is intended to protect the confidentiality of communications transmitted by one party to counsel for another party where a common defence effort or strategy has been decided and implemented by the parties and their respective counsel.  No good discussion of DDAs begins without first discussing the doctrine of the common interest; A concept that breathes life into all JDEs. The common interest doctrine (sometimes also called joint defense privilege) is an extension of solicitor-client privilege. It allows parties who have a common interest in defeating a mutual opponent of the right, to freely share information without having to worry about renouncing legal privilege with respect to their communication. A joint defense agreement, which simply states that the parties are co-accused and want to exchange information, may not be enough to protect the privilege.
Some courts are skeptical of efforts to hide behind a privilege that has been waived and are reluctant to extend the privilege to third parties in the absence of evidence that such an extension is supported. Common defence privilege does not only protect statements from lawyer to client or from lawyer to lawyer. The privilege also applies to communications addressed to certain agents of a lawyer, including accountants, who have been recruited to support the provision of legal services.  In addition, a person is not a party to the trial to be a party to a joint defence agreement. Common defence privilege also applies to „parties or potential parties having a common interest in the outcome of a given claim.  Only communications which are made within the framework of an ongoing joint venture and which aim to move the undertaking forward are protected.   There will be cases where a co-accused will attempt to monopolize the direction of the legal strategy in the context of a JDA solely to use himself. The cooperating defense attorney should be tired of these situations, as a court may find that there is no JDA in such circumstances. In Stepney, several defendants had been charged with violating several drug and gun laws.