Duets, Not Solos: The McLachlin Court's Co-Authorship Legacy

This article explores the recentphenomenon of the formal co-authorship of Supreme Court decisions. It begins with a short history of the practice, primarily in the closing years of the Lamer Court but expanding steadily under McLachlin. A closer investigation reveals two critically important dimensions: first, the practice is skewed toward the Court's more important decisions (measured in terms of subject matter legal complexity, interveners, and subsequent citation); and second, its diffusion across the Court's membership refutes the possibility that it simply reinforces persisting cleavages. This new practice represents a more overtly collegial format directed to the Court's more significant decisions. At the same time, however it diffuses traditional judicialaccountability anchored in the solo attribution of reasons for judgment. In conclusion, the article suggests that the emergence of the coauthorship style should be seen as a new "thirdphase" in the historical evolution of the Court's judgment-presentationstyle.