The article attempts to apply a socio-cultural approach to understanding the dynamics of the legal system. It is argued that the legal system, being an integral part of the socio-cultural environment, develops under its direct influence. The mechanism of such development is socio-cultural selection — the dependence of the viability of legal phenomena on their compliance with the system of values established in society. The key characteristics of socio-cultural selection are subjectivity, purposefulness, and activity. It is pointed out that, like selection in nature, socio-cultural selection performs a stabilizing and driving function, causing the preservation or change of certain parameters of the legal system.