The common interest doctrine can assure continued protection of certain communications that would otherwise be unprotected or deemed to waive the attorney-client privilege: communications between separate parties represented by their own lawyers who share an identical legal interest. Although courts differ on the exact contours of the common interest doctrine, some courts apply it very broadly.
For example, in the recent case of Carfagno v. Jackson Nat’l Life Ins. Co., No. 5:99cv 118, 2001 U.S. Dist. LEXIS 1768, at *20 (W.D. Mich. Feb. 13, 2001), the court held that what it called the “joint defense privilege” (more commonly now called the “common interest doctrine”) could apply to communications between the parties themselves, even if the defendant’s own lawyer did not attend the meeting.
Lawyers hoping to rely on the common interest doctrine should become familiar with the scope of the doctrine as recognized by the courts in which the lawyers are litigating. The pertinent court’s articulation of the common interest doctrine could affect such seemingly mundane matters as whether the lawyers must attend meetings between the clients sharing the common interest.