Law today constitutes an area of intense interdisciplinary research. An example of such research may be the economic analysis of law. The author understands the concept of law as law in action defined as the process of law formation and execution. Such a construction of law arises from democracy and the rule of law which, when considered independently, allow to analyse the relations between them. Next, the rule of law is analysed as a gradable concept, and the study on the influence of law on the rate of investments, the development of the financial sector, the increase in productivity and the ownership structure of firms and the availability of capital are presented. The influence of administrative legal regulations on people's behaviour and economic development (including, among others, moral hazard, social cost of extensive social protection and reasons for unemployment) is also shown. Concluding, the author draws our attention to the results of some empirical studies carried out recently worldwide and encourages similar studies to be carried out in Poland.