Within the framework of American Legal Realism, Frank’s jurisprudence focused on the judge’s decision-making process, emphasising its authoritative character. Using arguments developed from Freudian psychoanalysis and Piaget’s educational theories, the thesis of the unpredictability of judicial decisions goes so far as to falsify the principle of legal certainty. This essay discusses how Frank’s position gives rise to a broader field of research, regarding the need to reform the American judicial system of the time, in order to safeguard its democratic model.