As an institutional expression of judicial democracy,the lay participation system is inherently embedded within a professional judicial structure,thereby establishing an institutional connection between judicial democracy and professionalism.Representative democracy,participatory democracy,and deliberative democracy are the conceptual threads of judicial democracy,while the specialization of institutional organization and the professional nature of personnel allocation embody the essence of judicial professionalism.The competitive yet symbiotic relationship between judicial democracy and professionalism runs through the entire historical evolution of the lay participation system around the world,including China,demonstrating an ebb and flow of developmental dynamics in the course of history.The technical superiority model and the political superiority model represent two directions of judicial reforms.They influence the power equilibrium between judicial democracy and professionalism and also shape the specific configuration of the lay participation system.The interplay between democratization and professionalism forms a mid-level theoretical lens for understanding the evolution of the lay participation system.